Reversi strategy guide
Finish with more discs of your colour on the board than your opponent.
The rules in brief
- The 8×8 board starts with four discs in the centre. Black moves first.
- Place a disc so that it brackets one or more straight lines of your opponent's discs between the new disc and another of yours. Every bracketed disc flips to your colour.
- If you have no legal placement, you must pass. You may not pass when a placement exists.
- The game ends when neither player can move. The player with more discs wins; equal counts are a draw, which does not clear a level.
Strategy
- Corners are permanent
- A disc in a corner can never be flipped. Avoid giving your opponent access to an empty corner.
- Beware the X-squares
- The squares diagonally next to an empty corner (B2, G2, B7, G7) often hand that corner to your opponent.
- Mobility beats material
- Early on, having more legal moves matters more than having more discs. Quiet moves that flip few discs keep your options open.
- Stable edges
- Edge discs anchored to a corner become stable. Build edges that cannot be turned back.
- Parity at the end
- Late in the game, try to make the last move in each empty region. Count the empty squares in each region before you commit.
What each level teaches
- The First Flip: Identify a legal placement and flip a disc.
- The Opening Balance: Limit early exposure while choosing legal flips.
- Mobility Matters: Leave yourself future options.
- Corner Access: Keep risky squares near empty corners under control.
- Stable Edges: Aim for discs that are hard to turn back.
- The Quiet Move: Trade immediate disc count for future moves.
- Edge Trade: Compare edge patterns and move access.
- Parity Pressure: Count empty regions before a late move.
- Two Corners at Risk: Control the order in which corners become available.
- Last Empty Regions: Convert an endgame under an exact-search opponent.