Outflank and flip your opponent’s discs. Whoever owns more discs at the end wins.

How to play

Black moves first. Small dots show your legal moves (turn them off with Hints).
Place a disc so that one or more straight lines of enemy discs are trapped between your new disc and another of yours. All trapped discs flip to your colour.
If you have no legal move, you pass. The game ends when neither player can move.

Strategy tips

Corners are gold. A corner disc can never be flipped and anchors whole edges.
Avoid the X-squares – the squares diagonally next to an empty corner. Playing there often hands your opponent the corner.
Fewer discs early is fine. In the opening, flipping many discs gives your opponent more options. Focus on limiting their moves (mobility).
Count parity at the end. In the last dozen moves, try to make the final move in each empty region.

Easy is mostly random. Medium plays positionally. Hard searches several moves ahead and plays the last ten moves perfectly.

They are almost identical. Othello is a trademarked version with a fixed starting position, which this game also uses.