Was that a while ago? Minesweeper's pretty easy.

Claude Opus 4.5: "Build minesweeper as an artifact, don't use react"

(Then "Fix it to work on mobile where right click isn’t a thing")

Play it here: https://tools.simonwillison.net/minesweeper

Transcript here: https://claude.ai/share/2d351b62-a829-4d81-b65d-8f3b987fba23