Emergent Evolver

You draw an animal. You never tell it how to walk.

That's the whole idea! You get a body editor — joints, bones, muscles, feet, a head — and then you hand your creature over to a neural network that starts from absolutely nothing. There's no animation in here anywhere and no scripted walk cycle. Every bit of movement is generated from scratch using neuroevolution.

Twenty-odd creatures have a go at the course you designed, the best few breed, and the network GROWS brand new neurons and connections as it learns. You can mess with the settings and let the bodies evolve right alongside the brains.

After a few dozen generations, something drags itself forward. After a few hundred, something walks but stumbles. After a thousand? You've got a sprinter!

Dev Note

My name is Jonjoe1001 and I've always been fascinated with emergent complexity and machine learning. This simulator will allow you to create creatures with weird and odd bodies and watch them transform into sprinting, jumping, swimming, etc. monsters.

The name of the game here is to give your creatures a body that evolution can mold, not the other way around! Have fun, good luck, and enjoy!

All donations are appreciated but not required.

Also check out more of my work and games over on my website:

Jonjoe1001.dev

Six courses, six brains

Running, jumping, obstacles, climbing, gaps, swimming. Every creature can have a go at all of them and keeps a SEPARATE brain for each one, so teaching it to swim costs it nothing back on land.

Watch it think

The brain panel draws the whole network live: senses down the left, muscles down the right, the grown neurons in between, and every wire lights up as it fires. The gait panel shows you which muscle pulls when, so you can actually watch a walk turn into a run. And the fitness chart shows the whole population closing in on a champion it can't beat yet.

A map of every way of moving

Evolution keeps one answer and throws the rest away — including the creature that hopped instead of walking and finished two metres behind. That always bugged me! So the gait archive keeps them ALL: a grid sorted by how a creature moves instead of how far it got, holding the best hopper, the best crawler and the best sprinter right next to each other.

Click any square to watch it. Breed from it if you like it better than the winner!

Edit the body without losing the brain

Add a tail to a creature you've trained for a thousand generations and it carries everything it knows across, rewiring itself around the new limb instead of starting over from noise.

Race them

Two creatures, same course, ten kilometres, both brains on screen at once.

Physics that makes cheating not work

A foot grips the ground and absorbs a landing. A bare joint scuffs and loses speed, so a creature that tries to walk on its shins pays for it. Muscles get tired when you hold them. And if the head touches the ground, the run is over.

None of that is a scoring penalty though! It's all just built into the world, so the exploits stop working instead of getting punished after the fact.

No install, no account, no engine

The whole thing is ONE HTML file. Everything saves right in your browser, and any creature exports as a single line of text you can paste back in anywhere. Send your best one to a friend!

Heads up: if your browser blocks storage inside embedded games, hit Export to keep what you've made.