Tsume Othello by theme

Browse endgame problems by their key move — taking a corner, an edge, or a counterintuitive X-square. Every answer is proven by exhaustive search.

Take an edge

Problems where the best move is on an edge — stable stones that are hard to flip and set up corner play.

385 problems
Take the corner

Problems where the best move is a corner. Corners can never be flipped back — the anchor of endgame value.

176 problems
X-square is best

Problems where an X-square (the diagonal square next to a corner) — normally avoided — is actually the best move once you read it out.

20 problems