KAIJUNK

One subreddit, team of monsters, one shared health bar—sealed by a secret spell. Mashing does nothing. Crack the cipher together in the comments and banish them all before dawn.

Comment

Inspiration

The best moments on Reddit are the ones where a bunch of strangers wander into a thread and solve something together. A mystery photo, a cryptic clue, a "what is this bug." Nobody organizes it. It just happens, in the comments. I kept looking at Reddit games and noticing that most of them sit next to that energy instead of using it. You play your little single-player thing, and the community is a leaderboard bolted on the side.

I wanted the opposite. A game where the community isn't decoration but the actual mechanism, where the only way to win is for a bunch of people to figure something out together. The pitch in my head was almost a dare. Put one monster in front of a whole subreddit, make its health bar shared, and hide the win condition behind a puzzle no single person can brute-force. If the answer lives in the comments, then the comments become the game. That was the seed.

What it does

Every night, KAIJUNK drops one monster on the whole subreddit. Everyone who fights it chips away at the same health bar. It's a raid boss, and the raid is the entire community.

The twist is the ward. Each beast is sealed by a secret three-rune sigil, an ordered chant of elemental hexes. A prophecy tells you which three runes are involved but never the order, so all you really have to crack is the sequence, one of six possibilities. Ordinary attacks barely scratch the beast (a wrong hex does 1 damage). Casting the runes in the right order shatters the seal for a massive hit. Your summoning circle lights up rune by rune as you get warm, so it plays like a hot-and-cold deduction puzzle. You can solve it alone, but you crack it far faster as a group once someone posts the order in the thread. Guess wrong too many times in a row and the beast feeds on the broken chants and heals, so flailing is worse than thinking.

You don't even have to open the game. Reply !fire, !void, or !storm in the comments (aliases like !ice and !bolt work too) and you cast a hex straight from the feed. The beast replies to you. And the monsters aren't mine. Players forge their own in The Forge, choosing the creature, its color, an aura, a trait like Armored or Colossal, and its own secret three-rune sigil, then vote each other's beasts into the arena. So the thing you fight tonight was probably built by someone in the sub.

Around that core is a whole living world. The beasts get harder the more the coven wins. The first five are a fair fight, and then difficulty compounds until deep beasts are titanic raids that need the entire subreddit. When the shared health crosses 75, 50, and 25 percent, the beast taunts the thread, so even a lurker scrolling by sees a raid in progress. The first person to crack each night's ward gets crowned in the comments. There are streaks, coven ranks, a Dawn Ritual that triples your first hex of the night, a Witching Hour before dawn, blood moons, a Hall of banished beasts, collectible Deeds, and escaped monsters that come back scarred and holding a grudge against whoever hurt them most.

How we built it

It's a Devvit Web app. A Hono server and a Phaser 4.2 client render right inside the Reddit post, with Redis as the shared brain. One health pool for the whole sub, tonight's secret sigil, the leaderboards, per-player streaks and XP, the Hall, and everyone's earned Deeds. Every bit of nightly content (the sigil, the district skyline, the blood-moon phase) is seeded deterministically from the night number, so the entire subreddit faces the exact same puzzle at the same time.

Realtime is what makes it feel like a raid instead of a turn queue. Every hex anyone casts is pushed to every open screen, so when the sub is active you watch the health bar drop from other people's hits in real time. The comment combat runs off a CommentSubmit trigger that pulls a !hex out of any comment, maps it to an element (aliases and all), and feeds it into the same damage code the in-app buttons use. A hex cast from the thread and a hex cast from the game are literally the same action. The trickiest part was making the bot answer real players without ever reacting to its own replies, which would have started an infinite self-casting loop. Every bot comment carries an invisible marker the trigger skips.

The look leans on Phaser 4.2's filters. Glow and displacement on the sigil, a half-second of slow motion when a ward shatters, procedural lightning splitting the sky. The monsters are animated sprite sets (idle, attack, hurt, death) recolored per creature by a tint system, so one base becomes dozens of distinct beasts. Even the sound effects are synthesized in code with the Web Audio API instead of shipped as files.

Challenges we ran into

The biggest problem was almost invisible, and it nearly sank the whole thing. My first version let any hex chip the boss. It looked fine and played completely hollow. It was a clicker wearing a cool coat. The fix was to rebuild the entire damage economy around the cipher. A wrong hex does 1, a correct rune in sequence does 9, a full shattered spell does 50, and mindless mashing heals the beast. That made cracking the sigil the whole point. But widening that gap created a new danger. If the puzzle were too hard, a lone visitor would just bounce off a wall. So I leaned on the prophecy to narrow the answer to three known runes and made the summoning circle light up rune by rune. It stays solvable solo in about a minute and gets electric with a group.

Balancing solo against community was its own puzzle. The beast's health scales with how many people fought the night before, and it compounds with every win, so a busy sub faces a tougher beast than a quiet one. To avoid a death spiral where a struggling community gets pounded into oblivion, I keyed the escalation to wins only. Losing a night never makes the next beast harder. And I gave the first five beasts a grace period, so newcomers and cold judges always get a winnable fight before the difficulty climbs toward brutal.

There were plenty of smaller battles. The comment loop needed lenient parsing so !fire, !flame, and !burn all work. A nasty navigation bug would black-screen the whole app if you clicked Build, then Vote, then Build again, because a destroyed text object from the previous visit was getting reused. I found it by clicking around like a bored judge would, which is the only reason it didn't ship. And the strangest challenge of all was testing a community game by myself, late at night, trying to feel a crowd that isn't there yet.

Accomplishments that we're proud of

The comment section actually becomes the game. Somebody cracks the order, drops it in the thread, and the rest of the sub piles on to finish the beast before dawn. That exact moment was the one I was chasing from the first sentence of the pitch, and the first time I watched live !fire replies land and get answered back, it clicked that the thing worked.

I'm also proud that it doesn't scream "made with AI." It has its own dark, warm, gothic identity, it fits a phone screen, and the beasts are hand-animated sprites instead of mismatched stills. A first-time visitor can figure out what to do without a wall of instructions. The prophecy line and the "the ward is uncracked, be the first" nudge do a lot of quiet teaching. Getting a game this systemic to still feel legible in a few seconds was the part I sweated the most.

What we learned

Depth doesn't come from piling on features. It comes from making the one thing you do actually matter. I kept bolting systems onto this game, streaks and ranks and blood moons and grudges, and it still felt thin right up until I fixed the core decision. The moment a wrong hex meant something and cracking the sigil meant everything, all those other systems suddenly had a spine to hang on.

I also learned what "Reddit-y" really means, and it has nothing to do with karma jokes or Snoo cameos. It means giving a community a real reason to act together and a place, the comments, to do it. The most Reddit-y thing in my game isn't a reference to Reddit. It's a stranger posting "the order is void, blood, storm" and forty people acting on it. And I learned, again, that you find the bugs that matter by playing your own game like an impatient stranger would.

What's next for KAIJUNK

Spells that bend their own rules. Reversed chants, four-rune sigils on blood moons, beasts that re-seal themselves with a fresh ward halfway through a fight. Coven versus coven, where two subreddits race the same monster and the leaderboard is a map. And seasonal legendaries forged from the community's highest-voted creations, so the scariest things in the game are the ones the players made. Which is exactly how it should be.

Built With

Share this project:

Updates