Play

Reversi

Black moves first. Every move must flip at least one disc.

How to play

Played on an 8×8 board. Black moves first and the sides alternate.
A move must place a disc so that it brackets one or more opponent discs in a straight line (horizontal, vertical or diagonal) between the new disc and one of your own.
Every bracketed disc flips to your colour. A move that flips nothing is not allowed.
If you have no legal move you pass; if neither side can move, the game ends.
When the board is full or play is blocked, the side with more discs wins.

Tap or click a square to place a disc. Enable Hints to see the legal squares.
Arrow keys move the focus around the board; Enter or Space places a disc on the focused square.
Ctrl/⌘+Z or the Undo button takes back your last move; Escape closes an overlay.

Corners can never be flipped, so they are the strongest squares. Avoid giving them away.
Early on, fewer discs often means more mobility: do not chase a big count too soon.