Easy is genuine random — beatable every game. Medium plays the obvious wins and blocks. Hard runs full minimax over the 9-cell tree, which means perfect play. The best you can do is draw.
The hint button flashes the optimal next square. Charges scale with difficulty (3/2/1) — hard-mode hints are precious. Win/loss/draw stats live in localStorage, separately per difficulty.
Changes apply live — the embed link on the right and the preview above update instantly.
/embed.Embed link.