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More suspects!

Posted by
Sunday, August 30th, 2015 3:47 pm

I updated the post-compo version of my procedural puzzle game, “You! Are the monster” so it can now do bigger puzzles, with 5 suspects instead of 4!

Screen Shot 2015-08-30 at 1.21.46 PM

You can play the compo version or the post-compo version with its new 5-people mode. It still also has the “preschool” version for your kid!

How to make procedural puzzles

Posted by
Saturday, August 29th, 2015 11:57 pm

I’d like to share what I did in my game to procedurally generate puzzles. The cool thing is that this technique is quite general, so it may work for your games as well. If you’d like to, you can play “You! Are the monster” before reading on.

In my case I generate a “whodunit” type puzzle. There are four people and they say things about where they were, what they wore, and who they saw. Sometimes it’s vague, like “I saw someone tall at the bar”. The bad guy is a monster, of course, and they can lie but no one else does.

We can’t just generate those statements entirely at random, because some puzzles may end up unsolvable. So here’s what I do instead.

I start with only a few statements – one per person. I pick those at random. Then, I try to solve the puzzle (more on this later). If there is more than one person who could be the monster, then I add more statements. If instead no one can possibly be the monster, I start over. This eventually leads to finding a solvable puzzle.

Then I trim it down, removing statements that are not necessary to the puzzle being solvable. This results in a puzzle that is hopefully fun to solve.

One thing I only realized after the compo deadline is that this technique sometimes generates trivial puzzles, where the monster says things that contradict themselves. I fixed this is the post-compo version.

Now, you may ask, how do I solve the puzzle? I use brute force. Each randomly-generated statement is not only a bit of text, but also a bit of code that can check if what it says is true. I cycle through every possible choice for who is the monster, and then look for a combination of choices (people,location,color) such that every non-monster person tells the truth. If I find one then it means that that particular monster can be a solution. There can be either zero, one, or more solutions. I stop as soon as I find two since I know that’s not a puzzle I’ll want to keep. So a good puzzle has exactly one solution: if I remove the monster, then there exists a scenario that means everyone else tells the truth. If I pick anyone else as the monster then the remaining statements (including the actual monster’s) don’t go together – there is no scenario where they can all be true at the same time.

Surprisingly enough, this generation is fast enough that I can run it at the client as you load the page, and I didn’t even feel the need to put up an animated spinner or other “please wait” indicator. For more complicated problems, though, this may become necessary.

So there you go! With this simple technique you too can generate procedural puzzles to add to your game. Let me know what you think in the comments!

Kid version of “Find the monster!”

Posted by
Saturday, August 29th, 2015 4:52 pm

Can you adapt a puzzle detective game for preschool children? Yes! I made a special version of “You! Are the monster” for kids. The puzzle is now age-appropriate and the font nice and big. Plus it still works nicely on your phone!


Screen Shot 2015-08-29 at 2.48.48 PM


Go check it out! And you can compare this version to the original one, which you can still rate!

OMG I finished!

Posted by
Sunday, August 23rd, 2015 8:46 pm

Enjoy the programmer graphics and sound effects! The presentation of my detective puzzle game is minimalist, but what’s very cool is that it can procedurally generate thousands of problems, and find their solution too!

The game is called “You! Are the monster” because that’s what you say as you point to the correct person once you’ve solved the puzzle.

Here’s what it looks like:


Now go check it out! And then let me know what you think, and ideas for improvement (besides adding music; I ran out of time!).

Procedural detective game!

Posted by
Sunday, August 23rd, 2015 4:05 pm

I’m working on a procedural detective game. No screenshots yet, but I have code to generate a puzzle, make sure it’s solvable, and figure out who’s the monster.

Now adding programmer graphics! Be very afraid.

I’m in!

Posted by
Friday, August 21st, 2015 10:25 pm

No idea yet, but then again I just started.

Thermonuclear War now with tab completion!

Posted by
Sunday, January 4th, 2015 11:59 am

I updated my game, Thermonuclear War, with a post-compo version that adds two hotly requested features: scrolling and tab completion.

So now it’s easier than ever to play at being a hacker! The tab key will autocomplete the command, and the up arrow will go back to the previous command. Sadly, those only work in Firefox.

Check it out!


Some of my favorite games!

Posted by
Wednesday, December 24th, 2014 10:35 pm

Here are some of my favorites among the games I played for LD! I’m only included the ones I got through random judging, not the ones I saw from other recommendations, to keep things varied.

Games in no particular order.

Information Superhighway 1983. – painful yet cool!

Clickity Click. – addictive!

Square Dance. – swift action!

Test Subject #4218. – nice puzzle game!

Trapped? – original puzzle platformer!

Alien Harvesting Simulator – tower defense

The Operator – bare bones but lots of potential

Behind the screen – great use of the theme!

The Murderdome – exactly what you think it is!

Break the limits! – story-based progress quest.


Congratulations to everyone – it’s amazing to see what people can do in so little time!

And of course if you’re so inclined, check out Thermonuclear War, my fun hacking simulator!

Thermonuclear War post-compo version

Posted by
Thursday, December 11th, 2014 10:11 pm

If you haven’t rated my game yet, do that first! It’s a fun “hacking simulator”.

But if you have, you can now also check out the post-compo version. It adds a few nice touches like a transcript, support for the “up” arrow to repeat the last text (Firefox only, somehow), and a few small touches. Let me know how you like it! I plan on adding a bit more to it, it’ll show up at the same URL.

I’m going to post my favorites!

Posted by
Wednesday, December 10th, 2014 5:59 pm

I’m going to post my favorites in a few days. There are so many games! It’s really amazing.

My plan is to post about my favorites that are not already someone else’s favorites, in order to give exposure to more games.

Thermonuclear War walkthrough

Posted by
Tuesday, December 9th, 2014 6:32 pm

I am so thankful for all the positive feedback, and encouragement! I see people playing through all three levels of my game, it’s wonderful!

In case you’ve played it before but got stuck, I posted a walkthrough for level 3, so you can get unstuck!

You can get to level 3 directly by clicking on the words “level 1” at the bottom-left and choosing level 3 on the menu that appears.

Thank you! Have fun!

I submitted my game! Come play it!

Posted by
Sunday, December 7th, 2014 8:25 pm

Yay, it’s such a good feeling to finish a game!

Come check it out!

It’s a text game in the style of “War Games”: can you hack the computer and stop world war 3?

Here’s a trick as a “thank you” for reading so far: when you connect to a computer, you can put the password on the same line!

Have fun!

Thermonuclear War: last version before submit!

Posted by
Sunday, December 7th, 2014 6:05 pm

Final version of the game before submission!

It has three complete levels, there is a lot of fun packed in this little screen! You can click the “level” indicator on the bottom-left to change the level.

Play Thermonuclear War! It’s javascript, should work everywhere.

Here’s the game description:

“You race to the computer room, but you’re too late: the launch sequence for the nuclear missiles has already been initiated! As the numbers count down on the screen, you randomly try pressing buttons. And there, miracle! The computer responds.

To win, you have to hack the system to prevent global thermonuclear war.

Oh, there’s one little bug: the screen doesn’t scroll. Once you get to the bottom, you’re stuck and that’s the end of it. You only have one screen.

Good luck!”

Now I’m going to replace all assets with my own, so I can submit to the compo! Wish me luck!

Thermonuclear War comes to your mobile!

Posted by
Sunday, December 7th, 2014 10:32 am

I added a degree of mobile support for my game.

It’s really just a little text bar that’ll bring up the software keyboard. The game’s probably still much more comfortable with a keyboard, but if all you have is a phone/tablet, now you can at least give it a try!

Thermonuclear War – now with levels!

Posted by
Saturday, December 6th, 2014 7:24 pm

My game works, and I added a second level! Sounds too, plus other improvements.

The idea is that you are in a nuclear silo bunker, and someone just started the countdown – if you don’t stop it, nuclear war will end the world! You have to figure out what to type on the computer to stop the apocalypse. The whole game plays on this one screen. So much so, in fact, that the computer freezes if you run off the screen! You may have to reload the page and play a few times before you can win.

Play level 1 or Play level 2 (it should work on all browsers except mobile).

Thank you very much for playing, enjoy the game! If you can, please give me feedback so I can improve the game before the deadline!

Thermonuclear War – first prototype is live!

Posted by
Saturday, December 6th, 2014 1:01 pm

I got a first prototype to work, it’s online!

The idea is that you are in a nuclear silo bunker, and someone just started the countdown – if you don’t stop it, nuclear war will end the world!

You have to figure out what to type on the computer to stop the apocalypse. The whole game plays on this one screen. So much so, in fact, that the computer freezes if you run off the screen! You may have to reload the page and play a few times before you can win.

Play it online now! And give me feedback so I can improve it before the deadline!

It should work on Firefox, Chrome, and Safari. It’s not really designed for mobile phones since the game revolves around typing.

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