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Engineering

How the Yumina engine works: the AI inside games, variables and rules, prompts and memory, multiplayer rooms, and the numbers we measured along the way.

• EngineeringAn AI Crazy Dave You Can Talk To in Plants vs. ZombiesHow Yumina wired a language model into the original Plants vs. Zombies engine running as WebAssembly. One HTTP call per line, a lawn snapshot in, a validated JSON reply out, eight favors the game approves in advance, a tin whose contents are fixed before you buy, and a 64 KiB notebook.Yumina · October 18, 2026 · 11 min read
• EngineeringHow We Put AI Events and Characters Inside Slay the Spire 2How the SpireTalk mod runs the Yumina engine inside Slay the Spire 2, gives each AI character three decisions per line, voices events and endings, and lets the game check every reward.Yumina · October 18, 2026 · 12 min read