Simon Willison generates a match-3 game with Claude Opus 5.5
What happened
On 15 October 2026, Simon Willison reported that he used the chat mode of the default Claude iPhone app to have Claude Opus 5.5 Max build a Three.js game called "Tree Appreciator", in which the player appreciates the differences between two algorithmically generated trees. According to the report, Claude took 3 hours 7 minutes to deliver a spot-the-difference game with music, animation and an achievement system, and it was quite playable. The earlier headline said Simon Willison generated a match-3 game with Claude Opus 5.5, while later reports describe the actual gameplay as spot-the-difference, so the two differ on game genre. The current state of play: Claude Opus 5.5 Max completed the Three.js game in 3 hours 7 minutes.
Written by AI from the reports · updated 20 h ago
Timeline
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- Simon WillisonTree Appreciator
Tool: Tree Appreciator Another game experiment with Claude. This one used the default Claude iPhone app (chat mode, not Claude Code mode) where I prompted Claude Opus 5.5 Max with: Build a three js game called "Tree appreciator" - it shows you two algorithmically generated trees and the game mechanics is about appreciating the differences between them.
Heat of this event
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