Story

I've long held a bit of nostalgia for the old PlayStation game Monster Rancher.

You could "discover" monsters by popping in any arbitrary CD in your house – music, a PS game, a PC game, whatever – and it would generate a monster based on the disc's metadata, and add it to your ranch. It was a game about collecting, breeding, and battling these monsters.

The generated monster usually had nothing at all to do with the disc's content, of course. There were some specific discs that were hard-coded in that would give you a relevant monster, but not a ton.

It was a fairly niche thing, though, and the death of CDs sort of killed the whole idea.

But now in the age of LLMs, it feels like maybe the time has come back around for something like this to be pretty fun again, so I've implemented it as an Agent Skill that:

1. accepts a URL and reads the content (or any input, really) 2. follows some standard guidance on generating monster JSON for it 3. uses a Gemini image model to generate a monster avatar 4. renders it all in a fun little trading card image 5. allows you to breed them into hybrids, battle them, and share them to Github Gists

This was mainly a scratch-my-own-itch nostalgia indulgence. I briefly considered doing this as a full blown site, but agent skills give a fair bit more interactive flexibility while not costing me a dime. You can just point your agent (Claude Code, etc) to aiwebb/llmonster-rancher and tell it to get going.

Hope y'all have fun with it.