Reversi
Flip lines of discs, claim the corners, and finish with the most.
Level 1: The First Flip. Play any legal move that flips a disc.
Rules
Goal: Finish with more discs of your colour on the board than your opponent.
- 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.
Controls: Legal squares are marked with a small dot. Tap or click one to place. With a keyboard, use the arrow keys and Enter.
The ten levels
Levels 1 to 7 are free and open one at a time. Levels 8 to 10 are expert challenges with Premium.
- The First Flip Identify a legal placement and flip a disc. Play any legal move that flips a disc. Available
- The Opening Balance Limit early exposure while choosing legal flips. Finish with more discs than the opponent. Locked
- Mobility Matters Leave yourself future options. Finish with more discs than the opponent. Locked
- Corner Access Keep risky squares near empty corners under control. Finish with more discs than the opponent. Locked
- Stable Edges Aim for discs that are hard to turn back. Finish with more discs than the opponent. Locked
- The Quiet Move Trade immediate disc count for future moves. Finish with more discs than the opponent. Locked
- Edge Trade Compare edge patterns and move access. Finish with more discs than the opponent. Locked
- Parity Pressure Count empty regions before a late move. Finish with more discs than the opponent. Premium
- Two Corners at Risk Control the order in which corners become available. Finish with more discs than the opponent. Premium
- Last Empty Regions Convert an endgame under an exact-search opponent. Finish with more discs than the opponent. Premium
Strategy tips
- 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.