Beating Children at Mastermind [Video]

This video accompanies a blog post of the same title. The content is basically the same – if you prefer videos, watch this video. If you prefer blog posts, go read the blog post. You might also like to play with my Mastermind solver or view the source code.

Also available on YouTube and Facebook.

Beating Children at Mastermind

This blog post is also available as a video. Would you prefer to watch/listen to me tell you about how I’ve implemented a tool to help me beat the kids when we play Mastermind?

I swear that I used to be good at Mastermind when I was a kid. But now, when it’s my turn to break the code that one of our kids has chosen, I fail more often than I succeed. That’s no good!

Black, white, brown, blue, green, orange and yellow Mastermind pegs in a disordered heap.
If you didn’t have me pegged as a board gamer… where the hell have you been?

Mastermind and me

Maybe it’s because I’m distracted; multitasking doesn’t help problem-solving. Or it’s because we’re “Super” Mastermind, which differs from the one I had as a child in that eight (not six) peg colours are available and secret codes are permitted to have duplicate peg colours. These changes increase the possible permutations from 360 to 4,096, but the number of guesses allowed only goes up from 8 to 10. That’s hard.

A plastic Mastermind board in brown and green; it has twelve spots for guessing and shows six coloured pegs. The game has been won on the sixth guess.
The set I had as a kid was like this, I think. Photo courtesy ZeroOne; CC-BY-SA license.

Or maybe it’s just that I’ve gotten lazy and I’m now more-likely to try to “solve” a puzzle using a computer to try to crack a code using my brain alone. See for example my efforts to determine the hardest hangman words and make an adverserial hangman game, to generate solvable puzzles for my lock puzzle game, to cheat at online jigsaws, or to balance my D&D-themed Wordle clone.

Hey, that’s an idea. Let’s crack the code… by writing some code!

Screenshot showing Mastermind game from WebGamesOnline.com. Seven guesses have been made, each using only one colour for each of the four pegs, and no guesses are corect; only red pegs have never been guessed.
This online edition plays a lot like the version our kids play, although the peg colours are different. Next guess should be an easy solve!

Representing a search space

The search space for Super Mastermind isn’t enormous, and it lends itself to some highly-efficient computerised storage.

There are 8 different colours of peg. We can express these colours as a number between 0 and 7, in three bits of binary, like this:

Decimal Binary Colour
0 000 Red
1 001 Orange
2 010 Yellow
3 011 Green
4 100 Blue
5 101 Pink
6 110 Purple
7 111 White

There are four pegs in a row, so we can express any given combination of coloured pegs as a 12-bit binary number. E.g. 100 110 111 010 would represent the permutation blue (100), purple (110), white (111), yellow (010). The total search space, therefore, is the range of numbers from 000000000000 through 111111111111… that is: decimal 0 through 4,095:

Decimal Binary Colours
0 000000000000 Red, red, red, red
1 000000000001 Red, red, red, orange
2 000000000010 Red, red, red, yellow
…………
4092 111111111100 White, white, white, blue
4093 111111111101 White, white, white, pink
4094 111111111110 White, white, white, purple
4095 111111111111 White, white, white, white

Whenever we make a guess, we get feedback in the form of two variables: each peg that is in the right place is a bull; each that represents a peg in the secret code but isn’t in the right place is a cow (the names come from Mastermind’s precursor, Bulls & Cows). Four bulls would be an immediate win (lucky!), any other combination of bulls and cows is still valuable information. Even a zero-score guess is valuable- potentially very valuable! – because it tells the player that none of the pegs they’ve guessed appear in the secret code.

A plastic Mastermind board in blue and yellow with ten guess spaces and eight pegs. The sixth guess is unscored but looks likely to be the valid solution.
If one of Wordle‘s parents was Scrabble, then this was the other. Just ask its Auntie Twitter.

Solving with Javascript

The latest versions of Javascript support binary literals and bitwise operations, so we can encode and decode between arrays of four coloured pegs (numbers 0-7) and the number 0-4,095 representing the guess as shown below. Decoding uses an AND bitmask to filter to the requisite digits then divides by the order of magnitude. Encoding is just a reduce function that bitshift-concatenates the numbers together.

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/**
 * Decode a candidate into four peg values by using binary bitwise operations.
 */
function decodeCandidate(candidate){
  return [
    (candidate & 0b111000000000) / 0b001000000000,
    (candidate & 0b000111000000) / 0b000001000000,
    (candidate & 0b000000111000) / 0b000000001000,
    (candidate & 0b000000000111) / 0b000000000001
  ];
}

/**
 * Given an array of four integers (0-7) to represent the pegs, in order, returns a single-number
 * candidate representation.
 */
function encodeCandidate(pegs) {
  return pegs.reduce((a, b)=>(a << 3) + b);
}

With this, we can simply:

  1. Produce a list of candidate solutions (an array containing numbers 0 through 4,095).
  2. Choose one candidate, use it as a guess, and ask the code-maker how it scores.
  3. Eliminate from the candidate solutions list all solutions that would not score the same number of bulls and cows for the guess that was made.
  4. Repeat from step #2 until you win.

Step 3’s the most important one there. Given a function getScore( solution, guess ) which returns an array of [ bulls, cows ] a given guess would score if faced with a specific solution, that code would look like this (I’m convined there must be a more-performant way to eliminate candidates from the list with XOR bitmasks, but I haven’t worked out what it is yet):

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/**
 * Given a guess (array of four integers from 0-7 to represent the pegs, in order) and the number
 * of bulls (number of pegs in the guess that are in the right place) and cows (number of pegs in the
 * guess that are correct but in the wrong place), eliminates from the candidates array all guesses
 * invalidated by this result. Return true if successful, false otherwise.
 */
function eliminateCandidates(guess, bulls, cows){
  const newCandidatesList = data.candidates.filter(candidate=>{
    const score = getScore(candidate, guess);
    return (score[0] == bulls) && (score[1] == cows);
  });
  if(newCandidatesList.length == 0) {
    alert('That response would reduce the candidate list to zero.');
    return false;
  }
  data.candidates = newCandidatesList;
  chooseNextGuess();
  return true;
}

I continued in this fashion to write a full solution (source code). It uses ReefJS for component rendering and state management, and you can try it for yourself right in your web browser. If you play against the online version I mentioned you’ll need to transpose the colours in your head: the physical version I play with the kids has pink and purple pegs, but the online one replaces these with brown and black.

Testing the solution

Let’s try it out against the online version:

As expected, my code works well-enough to win the game every time I’ve tried, both against computerised and in-person opponents. So – unless you’ve been actively thinking about the specifics of the algorithm I’ve employed – it might surprise you to discover that… my solution is very-much a suboptimal one!

A young boy sits cross-legged on the floor, grinning excitedly at a Mastermind board (from the code-maker's side).
My code has only failed to win a single game… and that turned out to because my opponent, playing overexcitedly, cheated in the third turn. To be fair, my code didn’t lose either, though: it identified that a mistake must have been made and we declared the round void when we identified the problem.

My solution is suboptimal

A couple of games in, the suboptimality of my solution became pretty visible. Sure, it still won every game, but it was a blunt instrument, and anybody who’s seriously thought about games like this can tell you why. You know how when you play e.g. Wordle (but not in “hard mode”) you sometimes want to type in a word that can’t possibly be the solution because it’s the best way to rule in (or out) certain key letters? This kind of strategic search space bisection reduces the mean number of guesses you need to solve the puzzle, and the same’s true in Mastermind. But because my solver will only propose guesses from the list of candidate solutions, it can’t make this kind of improvement.

Animation showing how three clues alone are sufficient to derive a unique answer from the search space of the original "break into us" lock puzzle.
My blog post about Break Into Us used a series of visual metaphors to show search space dissection, including this one. If you missed it, it might be worth reading.

Search space bisection is also used in my adverserial hangman game, but in this case the aim is to split the search space in such a way that no matter what guess a player makes, they always find themselves in the larger remaining portion of the search space, to maximise the number of guesses they have to make. Y’know, because it’s evil.

Screenshot showing a single guess row from Online Mastermind, with the guess Red, Red, Green, Green.
A great first guess, assuming you’re playing against a random code and your rules permit the code to have repeated colours, is a “1122” pattern.

There are mathematically-derived heuristics to optimise Mastermind strategy. The first of these came from none other than Donald Knuth (legend of computer science, mathematics, and pipe organs) back in 1977. His solution, published at probably the height of the game’s popularity in the amazingly-named Journal of Recreational Mathematics, guarantees a solution to the six-colour version of the game within five guesses. Ville [2013] solved an optimal solution for a seven-colour variant, but demonstrated how rapidly the tree of possible moves grows and the need for early pruning – even with powerful modern computers – to conserve memory. It’s a very enjoyable and readable paper.

But for my purposes, it’s unnecessary. My solver routinely wins within six, maybe seven guesses, and by nonchalantly glancing at my phone in-between my guesses I can now reliably guess our children’s codes quickly and easily. In the end, that’s what this was all about.

Printing Maps from Dungeondraft

I really love Dungeondraft, an RPG battle map generator. It’s got great compatibility with online platforms like Foundry VTT and Roll20, but if you’re looking to make maps for tabletop play, there’s a few tips I can share:

Screenshot showing Dungeondraft being used to edit a circular tower. The Export window is visible.
Tabletop players can’t zoom in and will appreciate you printing with good contrast.

Planning and designing

Dungeondraft has (or can be extended with) features to support light levels and shadow-casting obstructions, openable doors and windows, line-of sight etc… great to have when you’re building for Internet-enabled tabletops, but pointless when you’re planning to print out your map! Instead:

  • Think about scale: I’m printing to A4 sheets and using inch-size squares, so every 11 x 8 squares equates to one sheet of paper. Knowing this, I can multiply-up to a whole number of sheets of paper and this informs my decisions about how to best make use of the maps (and what will and won’t fit on my dining table!).
  • Focus on legibility: Your printer probably won’t have the same kind of resolution as your screen, and your players can’t “zoom in” to get details. Play with the grid styles (under Map Settings) to find what works best for you, and try not to clash with your floor patterns. If you’re printing in monochrome, use the “Printer-Friendly” camera filter (also under Map Settings, or in the Export Options dialog) to convert to gorgeous line-art. Make sure critical elements have sufficient contrast that they’ll stand out when printed or your players might walk right over that chest, campfire, or bookshelf.
  • Think about exposure: You don’t get digital “fog of war” on the tabletop! Think about how you’re going to reveal the map to your players: plan to print in multiple sections to put together, jigsaw style, or have card to “cover” bits of the map. Think about how the tool can help you here: e.g. if you’ve got multiple buildings the players can explore, use a higher “level” or roof layer to put roofs on your buildings, then print the relevant parts of that level separately: now you’ve got a thematic cover-up that you can remove to show the insides of the building. Go the other way around for secret doors: print the empty wall on your main map (so players can’t infer the location of the secret door by the inclusion of a cover-up) and the secret door/passage on the overlay, so you can stick it onto the map when they find it.
Monochrome map showing a crane tower and attached dwelling.
If you’re printing in black and white, line art can be a gorgeous look.

Printing it out

There’s no “print” option in Dungeondraft, so – especially if your map spans multiple “pages” – you’ll need a multi-step process to printing it out. With a little practice, it’s not too hard or time-consuming, though:

Screenshot showing a cavern map in Gimp, with the Export Image dialog open and PDF selected as the output format.
Gimp makes light work of converting a PNG into a PDF.

Export your map (level by level) from Dungeondraft as PNG files. The default settings are fine, but pay attention to the “Overlay level” setting if you’re using smart or complex cover-ups as described above.

To easily spread your map across multiple pages, you’ll need to convert it to a PDF. I’m using Gimp to do this. Simply open the PNG in Gimp, make any post-processing/last minute changes that you couldn’t manage in Dungeondraft, then click File > Export As… and change the filename to have a .pdf extension. You could print directly from Gimp, but in my experience PDF reader software does a much better job at multi-page printing.

Foxit print dialog showing a preview of a map printed across 6 sheets of A4 paper.
Check the print preview before you click the button!

Open your PDF in an appropriate reader application with good print management. I’m using Foxit, which is… okay? Print it, selecting “tile large pages” to tell it to print across multiple sheets. Assuming you’ve produced a map an appropriate size for your printer’s margins, your preview should be perfect. If not, you can get away with reducing the zoom level by up to a percent or two without causing trouble for your miniatures. If you’d like the page breaks to occur at specific places (for exposure/reveal reasons), go back to Gimp and pad one side of the image by increasing the canvas size.

Check the level of “overlap” specified: I like to keep mine low and use the print margins as the overlapping part of my maps when I tape them together, but you’ll want to see how your printer behaves and adapt accordingly.

Multiple sheets of A4 paper joined with a slight overlap by long strips of sticky tape.
The overlap provides stability, rigidity, and an explanation as to exactly what that character tripped over when they rolled a critical fail on a DEX check.

If you’re sticking together multiple pages to make a single large map, trim off the bottom and right margins of each page: if you printed with cut marks, this is easy enough even without a guillotine. Then tape them together on the underside, taking care to line-up the features on the map (it’s not just your players who’ll appreciate a good, visible grid: it’s useful when lining-up your printouts to stick, too!).

I keep my maps rolled-up in a box. If you do this too, just be ready with some paperweights to keep the edges from curling when you unfurl them across your gaming table. Or cut into separate rooms and mount to stiff card for that “jigsaw” effect! Whatever works best for you!

Miniatures on a cave map, with the D&D Player's Handbook acting as a paperweight.
Any hefty tome, e.g. the 5e Player’s Handbook, can act as a paperweight.

DNDle (Wordle, but with D&D monster stats)

Don’t have time to read? Just start playing:

Play DNDle

There’s a Wordle clone for everybody

Am I too late to get onto the “making Wordle clones” bandwagon? Probably; there are quite a few now, including:

Screenshot showing a WhatsApp conversation. Somebody shares a Wordle-like "solution" board but it's got six columns, not five. A second person comments "Hang on a minute... that's not Wordle!"
I’m sure that by now all your social feeds are full of people playing Wordle. But the cool nerds are playing something new…

Now, a Wordle clone for D&D players!

But you know what hasn’t been seen before today? A Wordle clone where you have to guess a creature from the Dungeons & Dragons (5e) Monster Manual by putting numeric values into a character sheet (STR, DEX, CON, INT, WIS, CHA):

Screenshot of DNDle, showing two guesses made already.
Just because nobody’s asking for a game doesn’t mean you shouldn’t make it anyway.

What are you waiting for: go give DNDle a try (I pronounce it “dindle”, but you can pronounce it however you like). A new monster appears at 10:00 UTC each day.

And because it’s me, of course it’s open source and works offline.

The boring techy bit

  • Like Wordle, everything happens in your browser: this is a “backendless” web application.
  • I’ve used ReefJS for state management, because I wanted something I could throw together quickly but I didn’t want to drown myself (or my players) in a heavyweight monster library. If you’ve not used Reef before, you should give it a go: it’s basically like React but a tenth of the footprint.
  • A cache-first/background-updating service worker means that it can run completely offline: you can install it to your homescreen in the same way as Wordle, but once you’ve visited it once it can work indefinitely even if you never go online again.
  • I don’t like to use a buildchain that’s any more-complicated than is absolutely necessary, so the only development dependency is rollup. It resolves my import statements and bundles a single JS file for the browser.

Taking a Jackbox Zoom Party to the Next Level

A love a good Jackbox Game. There’s nothing quite like sitting around the living room playing Drawful, Champ’d Up, Job Job, Trivia Murder Party, or Patently Stupid. But nowadays getting together in the same place isn’t as easy as it used to be, and as often as not I find my Jackbox gaming with friends or coworkers takes place over Zoom, Around, Google Meet or Discord.

There’s lots of guides to doing this – even an official one! – but they all miss a few pro tips that I think can turn a good party into a great party. Get all of this set up before your guests are due to arrive to make yourself look like a super-prepared digital party master.

1. Use two computers!

Two laptops: one showing a full-screen Zoom chat with Dan and "Jackbox Games"; the second showing a windowed copy of Jackbox Party Pack 8.
You can use more than two, but two should be considered the minimum for the host.

Using one computer for your video call and a second one to host the game (in addition to the device you’re using to play the games, which could be your phone) is really helpful for several reasons:

  • You can keep your video chat full-screen without the game window getting in the way, letting you spend more time focussed on your friends.
  • Your view of the main screen can be through the same screen-share that everybody else sees, helping you diagnose problems. It also means you experience similar video lag to everybody else, keeping things fair!
  • You can shunt the second computer into a breakout room, giving your guests the freedom to hop in and out of a “social” space and a “gaming” space at will. (You can even set up further computers and have multiple different “game rooms” running at the same time!)

2. Check the volume

3.5mm adapter plugged into the headphone port on a laptop.
Plugging an adapter into the headphone port tricks the computer into thinking some headphones are plugged in without actually needing the headphones quietly buzzing away on your desk.

Connect some headphones to the computer that’s running the game (or set up a virtual audio output device if you’re feeling more technical). This means you can still have the game play sounds and transmit them over Zoom, but you’ll only hear the sounds that come through the screen share, not the sounds that come through the second computer too.

That’s helpful, because (a) it means you don’t get feedback or have to put up with an echo at your end, and (b) it means you’ll be hearing the game exactly the same as your guests hear it, allowing you to easily tweak the volume to a level that allows for conversation over it.

3. Optimise the game settings

Jackbox games were designed first and foremost for sofa gaming, and playing with friends over the Internet benefits from a couple of changes to the default settings.

Sometimes the settings can be found in the main menu of a party pack, and sometimes they’re buried in the game itself, so do your research and know your way around before your party starts.

Jackbox settings screen showing Master Volume at 20%, Music Volume at 50%, and Full-screen Mode disabled

Turn the volume down, especially the volume of the music, so you can have a conversation over the game. I’d also recommend disabling Full-screen Mode: this reduces the resolution of the game, meaning there’s less data for your video-conferencing software to stream, and makes it easier to set up screen sharing without switching back and forth between your applications (see below).

Jackbox accessibility settings: Subtitles, Motion Sensitivity, and Extended Timers are turned on.
Turning on the Motion Sensitivity or Reduce Background Animations option if your game has it means there’ll be less movement in the background of the game. This can really help with the video compression used in videoconferencing software, meaning players on lower-speed connections are less-likely to experience lag or “blockiness” in busy scenes.

It’s worth considering turning Subtitles on so that guests can work out what word they missed (which for the trivia games can be a big deal). Depending on your group, Extended Timers is worth considering too: the lag introduced by videoconferencing can frustrate players who submit answers at the last second only to discover that – after transmission delays – they missed the window! Extended Timers don’t solve that, but they do mean that such players are less-likely to end up waiting to the last second in the first place.

Jackbox game content settings; "Filter US-centric content" is switched on.
Finally: unless the vast majority or all of your guests are in the USA, you might like to flip the Filter US-Centric Content switch so that you don’t get a bunch of people scratching their heads over a cultural reference that they just don’t get.

By the way, you can use your cursor keys and enter to operate Jackbox games menus, which is usually easier than fiddling with a mouse.

4. Optimise Zoom’s settings

MacOS desktop showing a Jackbox game running and Zoom being configured to show a "portion of screen".
A few quick tweaks to your settings can make all the difference to how great the game looks.

Whatever videoconferencing platform you’re using, the settings for screen sharing are usually broadly similar. I suggest:

  • Make sure you’ve ticked “Share sound” or a similar setting that broadcasts the game’s audio: in some games, this is crucial; in others, it’s nice-to-have. Use your other computer to test how it sounds and tweak the volume accordingly.
  • Check “Optimize for video clip”; this hints to your videoconferencing software that all parts of the content could be moving at once so it can use the same kind of codec it would for sending video of your face. The alternative assumes that most of the screen will stay static (because it’s the desktop, the background of your slides, or whatever), which works better with a different kind of codec.
  • Use “Portion of Screen” sharing rather than selecting the application. This ensures that you can select just the parts of the application that have content in, and not “black bars”, window chrome and the like, which looks more-professional as well as sending less data over the connection.
  • If your platform allows it, consider making the mouse cursor invisible in the shared content: this means that you won’t end up with an annoying cursor sitting in the middle of the screen and getting in the way of text, and makes menu operation look slicker if you end up using the mouse instead of the keyboard for some reason.

Don’t forget to shut down any software that might “pop up” notifications: chat applications, your email client, etc.: the last thing you want is somebody to send you a naughty picture over WhatsApp and the desktop client to show it to everybody else in your party!

Tick Tock

Looking for something with an “escape room” vibe for our date night this week, Ruth and I tried Tick Tock: A Tale for Two, a multiplayer simultaneous cooperative play game for two people, produced by Other Tales Interactive. It was amazing and I’d highly recommend it.

Tick Tock screenshot showing a mysterious machine with many buttons. The machine is switched on and the screen shows a wolf's head and the number "-2". The buttons show a bug, an hourglass, a snake, a wolf's head, a keyhole, a cog, a raven, a doll, and a section of railway track.
If you enjoyed the puzzles of Myst but you only want to spend about an hour, not the rest of your life, solving then, this might be the game for you.

The game’s available on a variety of platforms: Windows, Mac, Android, iOS, and Nintendo Switch. We opted for the Android version because, thanks to Google Play Family Library, this meant we only had to buy one copy  (you need it installed on both devices you’re playing it on, although both devices don’t have to be of the same type: you could use an iPhone and a Nintendo Switch for example).

Screenshot from Tick Tock: an old-fashioned wireless radio set produces a scramble of letters in the air.
I can’t read that text. But if I could, it still wouldn’t make much sense without my partner’s input.

The really clever bit from a technical perspective is that the two devices don’t communicate with one another. You could put your devices in flight mode and this game would still work just fine! Instead, the gameplay functions by, at any given time, giving you either (a) a puzzle for which the other person’s device will provide the solution, or (b) a puzzle that you both share, but for which each device only gives you half of the clues you need. By working as a team and communicating effectively (think Keep Talking and Nobody Explodes but without the time pressure), you and your partner will solve the puzzles and progress the plot.

(We’re purists for this kind of puzzle game so we didn’t look at one another’s screens, but I can see how it’d be tempting to “cheat” in this way, especially given that even the guys in the trailer do so!)

Nopepad showing handwritten notes including: "Ticket stub 00067", "Clock shop open 18th", and "Set clock 12".
You could probably play successfully without keeping notes, but we opted to grab a pad and pen at one point.

The puzzles start easy enough, to the extent that we were worried that the entire experience might not be challenging for us. But the second of the three acts proved us wrong and we had to step up our communication and coordination, and the final act had one puzzle that had us scratching our heads for some time! Quite an enjoyable difficulty curve, but still balanced to make sure that we got to a solution, together, in the end. That’s a hard thing to achieve in a game, and deserves praise.

Tick Tock screenshot: among other documents, we examine a schematic for the construction of a mechanical raven's wing.
The art style and user interface is simple and intuitive, leaving you to focus on the puzzles.

The plot is a little abstract at times and it’s hard to work out exactly what role we, the protagonists, play until right at the end. That’s a bit of a shame, but not in itself a reason to reject this wonderful gem of a game. We spent 72 minutes playing it, although that includes a break in the middle to eat a delivery curry.

If you’re looking for something a bit different for a quiet night in with somebody special, it’s well worth a look.

Twinebook – Printable Interactive Fiction

Twine 2 is a popular tool for making hypertext interactive fiction, but there’s something about physical printed “choose your own adventure”-style gamebooks that isn’t quite replicated when you’re playing on the Web. Maybe it’s the experience of keeping your finger in a page break to facilitate a “save point” for when you inevitably have to backtrack and try again?

Annabe enjoying Choose Your Own (Minecraft) Story books.
These are the first branching novels I’ve introduced her to for which she’s felt the need to take notes.

As a medium for interactive adventures, paper isn’t dead! Our 7-year-old is currently tackling the second part of a series of books by John Diary, the latest part of which was only published in December! But I worry that authors of printed interactive fiction might have a harder time than those producing hypertext versions. Keeping track of all of your cross-references and routes is harder than writing linear fiction, and in the hypertext

Hand-written note showing branching path story plan, from John Diary's Twitter.
John Diary tweeted about his process back in 2017 and it looks… more manual than I’d want.

Twinebook

So I’ve thrown together Twinebook, an experimental/prototype tool which aims to bring the feature-rich toolset of Twine to authors of paper-based interactive fiction. Simply: you upload your compiled Twine HTML to Twinebook and it gives you a printable PDF file, replacing the hyperlinks with references in the style of “turn to 27” to instruct the player where to go next. By default, the passages are all scrambled to keep it interesting, but with the starting passage in position 1… but it’s possible to override this for specific passages to facilitate puzzles that require flipping to specific numbered passages.

Thumb in the page of a Sorcery choose-your-own-adventure gamebook.
In some adventure games, keeping your thumb in the page feels like it’s essential.

Obviously, it doesn’t work with any kind of “advanced” Twine game – anything that makes use of variables, Javascript, etc., for example! – unless you can think of a way to translate these into the written word… which is certainly possible – see Fighting Fantasy‘s skill, stamina, luck and dice-rolling mechanics, for example! – but whether it’s desirable is up to individual authors.

If this tool is valuable to anybody, that’s great! Naturally I’ve open-sourced the whole thing so others can expand on it if they like. If you find it useful, let me know.

Twine screenshot showing many branching paths of the game "Inpatient".
Mapping a complex piece of interactive fiction is a job for a computer, not a human.

If you’re interested in the possibility of using Twine to streamline the production of printable interactive fiction, give my Twinebook prototype a try and let me know what you think.

The Ballad of John Crawford

Following the success of our last game of Dialect the previous month and once again in a one-week hiatus of our usual Friday Dungeons & Dragons game, I hosted a second remote game of this strange “soft” RPG with linguistics and improv drama elements.

Thieves’ Cant

Our backdrop to this story was Portsmouth in 1834, where we were part of a group – the Gunwharf Ants – who worked as stevedores and made our living (on top of the abysmal wages for manual handling) through the criminal pursuit of “skimming a little off the top” of the bulk-break cargo we moved between ships and onto and off the canal. These stolen goods would be hidden in the basement of nearby pub The Duke of Wellington until they could be safely fenced, and this often-lucrative enterprise made us the envy of many of the docklands’ other criminal gangs.

I played Katie – “Kegs” to her friends – the proprietor of the Duke (since her husband’s death) and matriarch of the group. I was joined by Nuek (Alec), a Scandinavian friend with a wealth of criminal experience, John “Tuck” Crawford (Matt), adoptee of the gang and our aspiring quartermaster, and “Yellow” Mathias Hammond (Simon), a navy deserter who consistently delivers better than he expects to.

Thieves' Cant tableau at the end of a game of Dialect, with cards strewn around the table.
Our second tableau was somehow more-chaotic than the first, even after I accidentally removed several cards before taking this picture!

While each of us had our stories and some beautiful and hilarious moments, I felt that we all quickly converged on the idea that the principal storyline in our isolation was that of young Tuck. The first act was dominated by his efforts to proof himself to the gang, and – with a little snuff – shake off his reputation as the “kid” of the group and gain acceptance amongst his peers. His chance to prove himself with a caper aboard the Queen Anne went proper merry though after she turned up tin-ful and he found himself kept in a second-place position for years longer. Tuck – and Yellow – got proofed eventually, but the extra time spent living hand-to-mouth might have been what first planted the seed of charity in the young man’s head, and kept most of his numbers out of his pocket and into those of the families he supported in the St. Stevens area.

The second act turned political, as Spiky Dave, leader of the competing gang The Barbados Boys, based over Gosport way, offered a truce between the two rivals in exchange for sharing the manpower – and profits – of a big job against a ship from South Africa… with a case of diamonds aboard. Disagreements over the deal undermined Kegs’ authority over the Ants, but despite their March it went ahead anyway and the job was a success. Except… Spiky Dave kept more than his share of the loot, and agreed to share what was promised only in exchange for the surrender of the Ants and their territory to his gang’s rulership.

We returned to interpersonal drama in the third act as Katie – tired of the gang wars and feeling her age – took perhaps more than her fair share of the barrel (the gang’s shared social care fund) and bought herself clearance to leave aboard a ship to a beachside retirement in Jamaica. She gave up her stake in the future of the gang and shrugged off their challenges in exchange for a quiet life, leaving Nuek as the senior remaining leader of the group… but Tuck the owner of the Duke of Wellington. The gang split into those that integrated with their rivals and those that went their separate ways… and their curious pidgin dissolved with them. Well, except for a few terms which hung on in dockside gang chatter, screeched amongst the gulls of Portsmouth without knowing their significance, for years to come.

Crop from Fine View of 1798 The Gunwharf Portsmouth Dockyard by E G Burrows

Playing Out

Despite being fundamentally the same game and a similar setting to when we played The Outpost the previous month, this game felt very different. Dialect is versatile enough that it can be used to write… adventures, coming-of-age tales, rags-to-riches stories, a comedies, horror, romance… and unless the tone is explicitly set out at the start then it’ll (hopefully) settle somewhere mutually-acceptable to all of the players. But with a new game, new setting, and new players, it’s inevitable that a different kind of story will be told.

But more than that, the backdrop itself impacted on the tale we wove. On Mars, we were physically isolated from the rest of humankind and living in an environment in which the necessities of a new lifestyle and society necessitates new language. But the isolation of criminal gangs in Portsmouth docklands in the late Georgian era is a very different kind: it’s a partial isolation, imposed (where it is) by its members and to a lesser extent by the society around them. Which meant that while their language was still a defining aspect of their isolation, it also felt more-artificial; deliberately so, because those who developed it did so specifically in order to communicate surreptitiously… and, we discovered, to encode their group’s identity into their pidgin.

Prison Hulks in Portsmouth Harbour by Ambrose-Louis Garneray

While our first game of Dialect felt like the language lead the story, this second game felt more like the language and the story co-evolved but were mostly unrelated. That’s not necessarily a problem, and I think we all had fun, but it wasn’t what we expected. I’m glad this wasn’t our first experience of Dialect, because if it were I think it might have tainted our understanding of what the game can be.

As with The Outpost, we found that some of the concepts we came up with didn’t see much use: on Mars, the concept of fibs was rooted in a history of of how our medical records were linked to one another (for e.g. transplant compatibility), but aside from our shared understanding of the background of the word this storyline didn’t really come up. Similarly, in Thieves Cant’ we developed a background about the (vegan!) roots of our gang’s ethics, but it barely got used as more than conversational flavour. In both cases I’ve wondered, after the fact, whether a “flashback” scene framed from one of our prompts might have helped solidify the concept. But I’m also not sure whether or not such a thing would be necessary. We seemed to collectively latch onto a story hook – this time around, centred around Matt’s character John Crawford’s life and our influences on it – and it played out fine.

And hey; nobody died before the epilogue, this time!

I’m looking forward to another game next time we’re on a D&D break, or perhaps some other time.

We Are The Martians

This week our usual Dungeons & Dragons group took a week off while our DM recovered from a long and tiring week. As a “filler”, I offered to facilitate a game of Dialect: A Game About Language and How It Dies, from Thorny Games, who I discovered through a Metafilter post about their latest free print-and-play game, Sign: A Game about Being Understood. Yes, all of their games about about language and communication; what of it?

Dialect

Dialect could be described as a rules-light, GM-less (it has a “facilitator” role, but they have no more authority than any player on anything), narrative-driven/storytelling roleplaying game based on the concept of isolated groups developing their own unique dialect and using the words they develop as a vehicle to tell their stories.

Dialect's rulebook and card deck.
It’s also super-pretty to leaf through and hold.

This might not be the kind of RPG that everybody likes to play – if you like your rules more-structured, for example, or you’re not a fan of “one-shot”/”beer and pretzels” gaming – but I was able to grab a subset of our usual roleplayers – Alec, Matt R, Penny, and I – and have a game (with thanks to Google Meet for videoconferencing and Roll20 for the virtual tabletop: I’d have used Foundry but its card support is still pretty terrible!).

The Outpost

A game of Dialect begins with a backdrop – what other games might call a scenario or adventure – to set the scene. We opted for The Outpost, which put the four of us among the first two thousand humans to colonise Mars, landing in 2045. With help from some prompts provided by the backdrop we expanded our situation in order to declare the “aspects” that would underpin our story, and then expand on these to gain a shared understanding of our world and society:

  • Refugees from plague: Our expedition left Earth to escape from a series of devastating plagues that were ravaging the planet, to try to get a fresh start on another world.
  • Hostile environment: Life on Mars is dominated by the ongoing struggle for sufficient food and water; we get by, but only thanks to ongoing effort and discipline and we lack some industries that we haven’t been able to bootstrap in the five years we’ve been here (we had originally thought that others would follow).
  • Functionalist, duty-driven society: The combination of these two factors led us to form a society based on supporting its own needs; somewhat short of a caste system, our culture is one of utilitarianism and unity.
Finished game board from The Outpost backdrop of our game of Dialect.
Our finished game board, or tableau.

It soon became apparent that communication with Earth had been severed, at least initially, from our end: radicals, seeing the successes of our new social and economic systems, wanted to cement our differences by severing ties with the old world. And so our society lives in a hub-and-spoke cave system beneath the Martian desert, self-sustaining except for the need to send rovers patrolling the surface to scout for and collect valuable surface minerals.

In this world, and prompted by our cards, we each developed a character. I was Jeramiah, the self-appointed “father” of the expedition and of this unusual new social order, who remembers the last disasters and wars of old Earth and has revolutionary plans for a better world here on Mars, based on controlled growth and a planned economy. Alec played Sandy – “Tyres” to their friends – a rover-driving explorer with one eye always on the horizon and fresh stories for the colony brought back from behind every new crater and mountain. Penny played Susie, acting not only as the senior medic to the expedition but something more: sort-of the “mechanic” of our people-driven underground machine, working to keep alive the genetic records we’d brought from Earth and keep them up-to-date as our society eventually grew, in order to prevent the same kinds of catastrophe happening here. “Picker” Ben was our artist, for even a functionalist society needs somebody to record its stories, celebrate its accomplishments, and inspire its people. It’s possible that the existence of his position was Jeramiah’s doing: the two share a respect for the stark, barren, undeveloped beauty of the Martian surface.

We developed our language using prompt cards, improvised dialogue, and the needs of our society. But the decades that followed brought great change. More probes began to land from Earth, more sophisticated than the ones that had delivered us here. They brought automated terraforming equipment, great machines that began to transform Mars from a barren wasteland into a place for humans to thrive. These changes fractured our society: there were those that saw opportunity in this change – a chance to go above ground and live in the sun, to expand across the planet, to make easier the struggle of our day-to-day lives. But others saw it as a threat: to our way of life, which had been shaped by our challenging environment; to our great social experiment, which could be ruined by the promise of an excessive lifestyle; to our independence, as these probes were clearly the harbingers of the long-promised second wave from Earth.

Even as new colonies were founded, the Martians of the Hub (the true Martians, who’d been here for yams time, lived and defibed here, not these tanning desert-dwelers that followed) resisted the change, but it was always going to be a losing battle. Jeramiah took his last breath in an environment suit atop a dusty Martian mountain a day’s drive from the Hub, watching the last of the nearby deserts that was still untouched by the new green plants that had begun to spread across the surface. He was with his friend Sandy, for despite all of the culture’s efforts to paint them as diametrically opposed leaders with different ideas of the future, they remained friends until the end. As the years went by and more and more colonists arrived, Sandy left for Phobos, always looking for a new horizon to explore. Sick of the growing number of people who couldn’t understand his language or his art, Ben pioneered an expedition to the far side of the planet where he lived alone, running a self-sustaining agri-home and exploring the hills until his dying day. We were never sure where Susie ended up, but it wasn’t Mars: she’d talked about joining humanity’s next big jump, to the moons of Jupiter, so perhaps she’s out there on one of the colonies of Titan or Europa. Maybe, low clicks, she’s even keeping our language alive out there.

Retrospective

The whole event was a lot of fun and I’m keen to repeat it, perhaps with a different group and a different backdrop. The usual folks know who they are, but if you’re not one of those and you want in next time we play, drop me a message of some kind.

Banners Begone!

This article is a repost promoting content originally published elsewhere. See more things Dan's reposted.

It’s a clicker quest of purging banners from your homepage!

Push through dozens of banners and upgrade various web-tools to grow your ad-blocking power.
Hone your clicking skills – matters are in your own fingers hands!

There’s no time for idling, show these ads their place!

I quite enjoyed this progressive game: it’s a little bit different than most, the theming is fun, it lends itself to multiple strategies, and it’s not geared towards making you wait for longer and longer intervals (as is common in this genre): there’s always something you can be doing to get closer to your goal.

You’ll need a mouse with left and right buttons.

Cheating Hangman

A long while ago, inspired by Nick Berry‘s analysis of optimal Hangman strategy, I worked it backwards to find the hardest words to guess when playing Hangman. This week, I showed these to my colleague Grace – who turns out to be a fan of word puzzles – and our conversation inspired me to go a little deeper. Is it possible, I thought, for me to make a Hangman game that cheats by changing the word it’s thinking of based on the guesses you make in order to make it as difficult as possible for you to win?

Play “Cheating Hangman”

The principle is this: every time the player picks a letter, but before declaring whether or not it’s found in the word –

  1. Make a list of all possible words that would fit into the boxes from the current game state.
  2. If there are lots of them, still, that’s fine: let the player’s guess go ahead.
  3. But if the player’s managing to narrow down the possibilities, attempt to change the word that they’re trying to guess! The new word must be:
    • Legitimate: it must still be the same length, have correctly-guessed letters in the same places, and contain no letters that have been declared to be incorrect guesses.
    • Harder: after resolving the player’s current guess, the number of possible words must be larger than the number of possible words that would have resulted otherwise.
Gallows on a hill.
Yeah, you’re screwed now.

You might think that this strategy would just involve changing the target word so that you can say “nope” to the player’s current guess. That happens a lot, but it’s not always the case: sometimes, it’ll mean changing to a different word in which the guessed letter also appears. Occasionally, it can even involve changing from a word in which the guessed letter didn’t appear to one in which it does: that is, giving the player a “freebie”. This may seem counterintuitive as a strategy, but it sometimes makes sense: if saying “yeah, there’s an E at the end” increases the number of possible words that it might be compared to saying “no, there are no Es” then this is the right move for a cheating hangman.

Playing against a cheating hangman also lends itself to devising new strategies as a player, too, although I haven’t yet looked deeply into this. But logically, it seems that the optimal strategy against a cheating hangman might involve making guesses that force the hangman to bisect the search space: knowing that they’re always going to adapt towards the largest set of candidate words, a perfect player might be able to make guesses to narrow down the possibilities as fast as possible, early on, only making guesses that they actually expect to be in the word later (before their guess limit runs out!).

Cheating Hangman
The game is brutally-difficult, but surprisingly fun, and you can have it tell you when and how it cheats so you can begin to understand its strategy.

I also find myself wondering how easily I could adapt this into a “helpful hangman”: a game which would always change the word that you’re trying to guess in order to try to make you win. This raises the possibility of a whole new game, “suicide hangman”, in which the player is trying to get themselves killed and so is trying to pick letters that can’t possibly be in the word and the hangman is trying to pick words in which those letters can be found, except where doing so makes it obvious which letters the player must avoid next. Maybe another day.

In the meantime, you’re welcome to go play the game (and let me know what you think, below!) and, if you’re of such an inclination, read the source code. I’ve used some seriously ugly techniques to make this work, including regular expression metaprogramming (using regular expressions to write regular expressions), but the code should broadly make sense if you want to adapt it. Have fun!

Play “Cheating Hangman”

Update 26 September 2019, 16:23: I’ve now added “helpful mode”, where the computer tries to cheat on your behalf rather than against you, but it’s not as helpful as you’d think because it assumes you’re playing optimally and have already memorised the dictionary!

Update 1 October 2019, 06:40: Now featured on MetaFilter; hi, MeFites!

Twee2 – Interactive Fiction Authoring for Geeks

There’s a wonderful tool for making web-based “choose your own adventure”-type games, called Twine. One of the best things about it is that it’s so accessible: if you wanted to, you could be underway writing your first ever story with it in about 5 minutes from now, without installing anything at all, and when it was done you could publish it on the web and it would just work.

Screenshot of a Twine 2 story map
A “story map” in Twine 2. Easy interactive fiction writing for normal people.

But the problem with Twine is that, in its latest and best versions, you’re trapped into using the Twine IDE. The Twine IDE is an easy-to-use, highly visual, ‘drag-and-drop’ interface for making interactive stories. Which is probably great if you’re into IDEs or if you don’t “know better”… but for those of us who prefer to do our writing in a nice clean, empty text editor like Sublime or TextMate or to script/automate our builds, it’s just frustrating to lose access to the tools we love. Plus, highly-visual IDEs make it notoriously hard to collaborate with other authors on the same work without simply passing it back and forwards between you: unless they’ve been built with this goal in mind, you generally can’t have two people working in the same file at the same time.

Sublime Text demonstrating multi-line-selection.
Now THIS is what code editing should look like.

Earlier versions of Twine had a command-line tool called Twee that perfectly filled this gap. But the shiny new versions don’t. That’s where I came in.

In that way that people who know me are probably used to by now, I was very-slightly unsatisfied with one aspect of an otherwise fantastic product and decided that the correct course of action was to reimplement it myself. So that’s how, a few weeks ago, I came to release Twee2.

Twee2 logo
Twee2’s logo integrates the ‘branching’ design of Twine adventures with the ‘double-colon’ syntax of Twee.

If you’re interested in writing your own “Choose Your Own Adventure”-type interactive fiction, whether for the world or just for friends, but you find user-friendly IDEs like Twine limiting (or you just prefer a good old-fashioned text editor), then give Twee2 a go. I’ve written a simple 2-minute tutorial to get you started, it works on Windows, MacOS, Linux, and just-about everything else, and it’s completely open-source if you’d like to expand or change it yourself.

(there are further discussions about the concept and my tool on Reddit here, here, here and here, and on the Twinery forums herehere and here)

Get Twee2

Post-It Minesweeper

Remember Minesweeper? It’s probably been forever since you played, so go have a game online now. And there went your afternoon.

A game of Microsoft Minesweeper in progress.
This is actually a pretty tough move.

My geek-crush Ben Foxall posted on Twitter on Monday morning to share that he’d had a moment of fun nostalgia when he’d come into the office to discover that somebody in his team had covered his monitor with two layers of Post-It notes. The bottom layer contained numbers – and bombs! – to represent the result of a Minesweeper board, and the upper layer ‘covered’ them so that individual Post-Its could be removed to reveal what lay beneath. Awesome.

Ben Foxall discovers Post-It Minesweeper
Unlike most computerised implementations of Minesweeper, the first move isn’t guaranteed to be safe. Tread carefully…

Not to be outdone, I hunted around my office and found some mini-Post-Its. Being smaller meant that I could fit more of them onto a monitor and thus make a more-sophisticated (and more-challenging!) play space. But how to generate the board? Sure: I could do it by hand, but that doesn’t seem very elegant at all – plus, humans make really bad random number generators! I didn’t need quantum-tunnelling-seeded Minesweeper (yes, that’s a thing) levels of entropy, sure, but it’d still be nice to outsource the heavy lifting to a computer, right?

Screenshot of my Post-It Minesweeper board generator.
Yes, I’m quite aware of the irony of using a computer to generate a paper-based version of a computer game, why do you ask?

So naturally, I wrote a program to do it for me. Want to see? It’s at danq.me/minesweeper. Just line up some Post-Its on a co-worker’s monitor to work out how many you can fit across it in each dimension (I found that I could get 6 × 4 standard-sized Post-Its but 7 × 5 or even 8 × 5 mini-sized Post-Its very comfortably onto one of the typical widescreen monitors in my office), decide how many mines you want, and click Generate. Don’t like the board you get? Click it again!

Liz McCarthy tweets about her experience of being given a Post-It Minesweeper game to play.
I set up the first game on my colleague Liz’s computer, before she came in this morning.

And because I was looking for a fresh excuse to play with Periscope, I broadcast the first game I set up live to the Internet. In the end, 66 people ended up watching some or all of a paper-based game of Minesweeper played by my colleague Liz, including moments of cheering her on and, in one weird moment, despair at the revelation that she was married. The internet’s strange, yo.

Anyway: in case you missed the Periscope broadcast, I’ve put it on YouTube. Sorry about the portrait-orientation filming: I think it’s awful, too, but it’s a Periscope thing and I haven’t installed the new update that fixes it yet.

Now go set up a game of Post-It Minesweeper for a friend or co-worker.