Neurox

I make playable games using only AI prompts. No team, no budget. Follow the journey.

[Neurox @_neurox]

the Mentos sim in this post pulled 350K+ views with people arguing over whether Opus got nerfed. so I built my own soda geyser with Claude to see what makes these look right. here's what mattered, plus the 3 things that broke mine.

1. what's actually simulated?
12,000 foam blobs and 5,000 droplets, each with gravity, air drag and wind. six sodas, up to 25 candies, a measuring pole next to the bottle.

2. how does it know how high to go?
the peak is predicted from soda, candy, count, temperature and nozzle. then the launch speed is solved so the fastest foam actually reaches that height.

3. why does the foam look like foam?
soft lit sprites while it flies, flattened blobs once it lands, wet stains painted where it hits.

the 3 mistakes:
→ solid spheres for foam. the first version looked like a jet of gravel
→ drag grows with speed squared. at 25 candies the jet came up 2 m short of the prediction until the launch speed was solved with the same drag
→ redrawing 18,000 particles on every physics step. the page froze, once per frame is enough

one run of one prompt tells you very little. the checks after it are what make the difference.

what should I simulate next?

playable in the reply ↓

[Ivana @ivanainai]

Has Opus 5.5 been quietly NERFED??

I reran the exact same Mentos simulation prompt from September 30 today.

Same model. Same prompt. 20 days apart.

Look at the difference. 💀

It looks like making the current model worse is the easiest way to make the next release look 10x better?

[Neurox @_neurox]

@AIDuckLabs Thanks! The trick is that the dense grass only follows the mower. Further out it switches to a lighter layer, so your laptop doesn't melt.

[Neurox @_neurox]

Night City running in Chrome is wild. My browser game is smaller, just one red lawn tractor and over 400,000 blades of grass.

Every blade under the deck gets cut. Straight stripes drop more coins, and the coins buy a wider deck and a faster engine. You start in a neighbor's backyard and work up to a stadium pitch.

It's still in development, built with AI in three.js. You can already play it: https://t.co/4D9QpXpA3B

[chasm @chasmmmmmmmmmmm]

CYBERPUNK 2077 NOW RUNS IN YOUR BROWSER 🚨

WTF IS GOING ON, HOW IS THIS POSSIBLE LOL

A dev called omonkeyzz got Night City running in Chrome using WebGPU. It's not cloud streaming. It runs on your own GPU, and the game streams in as you play.

[Neurox @_neurox]

@DarkFactorr Appreciate it. The link in the post is playable, so you can try it.

[Neurox @_neurox]

the Mentos sim in this post pulled 350K+ views with people arguing over whether Opus got nerfed. so I built my own soda geyser with Claude to see what makes these look right. here's what mattered, plus the 3 things that broke mine.

1. what's actually simulated?
12,000 foam blobs and 5,000 droplets, each with gravity, air drag and wind. six sodas, up to 25 candies, a measuring pole next to the bottle.

2. how does it know how high to go?
the peak is predicted from soda, candy, count, temperature and nozzle. then the launch speed is solved so the fastest foam actually reaches that height.

3. why does the foam look like foam?
soft lit sprites while it flies, flattened blobs once it lands, wet stains painted where it hits.

the 3 mistakes:
→ solid spheres for foam. the first version looked like a jet of gravel
→ drag grows with speed squared. at 25 candies the jet came up 2 m short of the prediction until the launch speed was solved with the same drag
→ redrawing 18,000 particles on every physics step. the page froze, once per frame is enough

one run of one prompt tells you very little. the checks after it are what make the difference.

what should I simulate next?

playable in the reply ↓

[Ivana @ivanainai]

Has Opus 5.5 been quietly NERFED??

I reran the exact same Mentos simulation prompt from September 30 today.

Same model. Same prompt. 20 days apart.

Look at the difference. 💀

It looks like making the current model worse is the easiest way to make the next release look 10x better?

[Neurox @_neurox]

@sajimayaa The dark soil rolling out behind the seeder is the whole appeal. I'm building the lawn version, and the stripes behind the mower scratch the same itch.

[Neurox @_neurox]

New York in 784KB is great, but somebody has to mow the lawns.

One backyard, one red tractor and about 230,000 blades of grass. Every blade under the deck gets cut, and the stripes go light or dark depending on where the camera looks from. Same engine, built with AI, runs in the browser.

It's a game in development. You take mowing jobs around town, straight stripes pay more, and the last lawn is a stadium.

[mrdoob @mrdoob]

Spent a bunch of tokens over the last few weeks building a fully procedural New York simulation.

https://t.co/YSrGNoIYsK

It's only 784KB gzipped and the code is on github, so you can do whatever you want with it ✌️

[Neurox @_neurox]

@shmidtqq 16 pixel robots as the control panel is such a good interface. agents become something you can check at a glance instead of a wall of logs. how does he spot the one that's stuck, does its sprite change?

[Neurox @_neurox]

@vib3coded for $10 that's a lot of world. I just built a soda geyser sim with Opus 5.5 where a breeze bends the jet and a pole measures the height, and toggles like your rain make these feel alive. does the rain change how the players move?

[Neurox @_neurox]

Play it in your browser: https://t.co/41pF4yyLrY

[Neurox @_neurox]

@sundyme @LexnLin synthesized nature sounds too is the bit that got me. I did the music for my city in a jar video the same way, chords and plucks generated straight into a wave file. how did you get water that doesn't just sound like plain noise?

[Neurox @_neurox]

@ivanainai same prompt 20 days apart can still land very differently, every run samples fresh. did you try it 3 or 4 times on each date? one run each way is hard to read.

[Neurox @_neurox]

@Mnilax 966 pokemon in a browser on a phone is a lot to keep smooth. how are you handling the sprites, one big atlas per region?

[Neurox @_neurox]

Play it in your browser: https://t.co/Za9W4FFiwc

[Neurox @_neurox]

Every tree in my City in a Jar is made in code, no Blender. Here's how, plus 2 mistakes that made the first version look fake.

1. the shape
a few spheres per tree, each pushed in and out with noise so the outline is lumpy, not round

2. the colour
darker at the bottom, lighter on top. that one gradient does most of the work

3. the count
6 tree shapes, copied across the whole town with random size and rotation

the 2 mistakes:
→ plain cones and balls. the first trees looked like a toy set, I threw them out
→ noise built from multiplied sine waves. on the clouds it showed up as a visible grid, smooth value noise fixed it

what would you build in code instead of modelling it?

the town is playable in the reply ↓

[Fork Dev @ForkedPush]

I asked Claude Opus 5.5 to make a bush for my game. Here’s the whole process in 30 seconds.

Tools: Unity, Blender, Blender MCP (by @sidahuj)

Game link in the reply 👇

[Neurox @_neurox]

@hxtnv44 the ragdolls are so good lol. would 100% play a quick browser version, drop a link when it’s playable!

[Neurox @_neurox]

@MeticulAi @threejs @AnthropicAI lol the AI beating its own creator is peak vibe coding. what’s the strategy that gets you closest to a win?

[Neurox @_neurox]

@Mornedkgames @3rdEchoSounds love the rhythm-style workout bar, didn’t expect a fitness minigame here. how many minigames are in it?

[Neurox @_neurox]

@3rdEchoSounds happy #DemoMonday! a living ant farm in glass 🐜 open brass valves to route the colony, grow it to unlock new chambers. runs in the browser: https://t.co/d2OTS95MtA

[Neurox @_neurox]

@DerekNee @deepseek_ai @threejs three.js games are getting so good. made an ant farm sim with opus and the physics took the most rounds, how was car handling with deepseek?

[Neurox @_neurox]

@anxuanng @claudeai @threejs love sims like this. building an ant farm in three.js rn and the pathing is killing me lol, how are you handling it?