Reversi
Trap discs to flip them. Most discs wins.
How to play Reversi
Reversi is played on an 8×8 board with discs that are dark on one side and light on the other. The game starts with four discs in the centre: two of each colour, placed diagonally. Dark moves first.
Making a move
- Place one disc of your colour on an empty square so that it outflanks one or more of your opponent's discs — a straight line of their discs with your new disc at one end and one of your existing discs at the other.
- Every outflanked disc is flipped to your colour. Lines can run horizontally, vertically or diagonally, and one move can flip discs in several directions at once.
- A move is only legal if it flips at least one disc. Legal squares are marked with a small dot on this board.
Passing
If you have no legal move, your turn is passed automatically and your opponent plays again. If neither player can move, the game is over.
Winning
When the board is full or nobody can move, the player with more discs of their colour wins. Equal counts are a draw.
Strategy tips
- Corners are everything. A disc on a corner can never be flipped. Most strong games are decided by who gets the corners.
- Avoid the squares next to empty corners. The diagonal neighbours of a corner (the “X-squares”) and the edge squares beside it (the “C-squares”) often give your opponent the corner.
- Fewer discs early can be better. Grabbing lots of discs in the opening usually gives your opponent more moves. Aim to limit their options instead — this is called mobility.
- Stay quiet. Prefer moves that flip discs in the interior and don't open new frontier squares for your opponent.
- Think about parity at the end. In the last empty regions, try to make the final move in each one.
Reversi FAQ
Is Reversi the same as Othello?
Othello is a trademarked version of Reversi with a fixed starting position. The rules played here — four centre discs placed diagonally, dark moves first — are the standard modern rules used by both.
What happens if I can't move?
Your turn passes automatically and the game tells you. If neither side can move, the game ends and discs are counted.
Why are some squares marked with dots?
The dots show every legal move for the player whose turn it is. It makes learning the game much faster.
How good is the Hard computer?
Hard looks several moves ahead and understands corners and mobility. Beating it consistently takes real Reversi strategy.
