Ch3ss
Chess, three boards deep.
Three stacked 8×8 boards. Knights hop levels, rooks climb, pawns promote on any back rank — and castling can carry your king two floors. Same pieces you know, a whole new dimension to master.
Proven rules
A complete 3D ruleset with an engine validated move-for-move against an independent reference — through more than a million positions. In 3D, a lone rook can't even checkmate. We proved it.
Learn the third dimension
A built-in tutorial teaches every piece's new powers, from vertical pawn pushes to two-level castling.
Play right now
Pass-and-play with a friend or take on the AI — free, in any browser, no account.