Do not feed empty corners
Squares beside an unclaimed corner are risky because they often let the opponent take that corner next.
Reversi Guide
Reversi Guide
Reversi is less about flipping the most discs now and more about choosing squares that stay safe later.
Board Control
Value safe edges later on
Once an edge can be held without giving something back, it becomes a strong base for the rest of the game.
Check the reply move first
Before placing your disc, look at which legal move you are opening for the computer on the next turn.