Othello (Reversi) Strategy: Why Flipping the Most Discs Loses

Most beginners play Othello by flipping as many discs as possible each turn. It feels like progress, but it usually loses — discs flip back and forth all game, and only the count on the very last move matters. Good Othello is about who can keep making good moves, not who is ahead in the middle.

Corners are forever

A disc in a corner can never be flipped — it is permanently stable and anchors the whole edge next to it. That makes corners the most valuable squares on the board. The flip side: avoid playing the squares diagonally next to an empty corner (the "X-squares"), and be careful with the edge squares beside a corner (the "C-squares"), because they often hand the corner to your opponent.

Mobility: keep your options open

Mobility means how many good moves you have. Strong play keeps your own choices open while shrinking your opponent's, until they are forced to play a bad square — next to a corner, or a move that gives you one. Counterintuitively, holding few discs in the early game can be strong, because it often means your opponent has fewer safe replies.

• Value corners highest — they can never be flipped.
• Avoid X-squares (diagonal to an empty corner); they leak corners.
• Prefer moves that reduce your opponent's good replies.
• Ignore the disc count until the very end.

The endgame is pure reading

In the last several moves the board is small and concrete, so you can — and should — read each line all the way to the final empty square and compare the totals. Parity (who is forced to move into the last empty region) and forced replies decide tight games. This is exactly the skill that endgame puzzles train.

How to practice

Forced-win Othello puzzles drill this endgame reading directly. On TsumeDojo the Tsume Othello problems give you a position to win by force and verify your line by exhaustive search, so you learn to read to the last square instead of grabbing discs.