Four in a Row — Strategy

Threats and double threats

A threat is an empty cell that would give you four in a row. A threat that can be taken right now (there is already a disc or the floor under it) is a win on the next move, and the opponent has to block it.

Double threat

If you have two threats that can both be taken at once, the opponent blocks only one — and you win with the other. Almost every game is decided this way. Look for a move after which you have two immediate threats, such as a three open on both sides in the bottom row: c1, d1, e1 with b1 and f1 empty.

Threats on top of each other

Two threats in the same column, one right above the other, cannot be blocked either: if the opponent takes the lower cell, you take the upper one. Such stacked threats are a strong weapon in the middle game.

Do not play under a threat

The most common mistake is dropping a disc into the cell right under an opponent threat. That makes the threat immediate, and the opponent wins. Before every move check what lies above the cell where your disc will land.

For the same reason a threat that cannot be taken yet is also valuable: it locks the column. Neither you nor the opponent wants to play under it, and towards the end of the game this decides who has to make a forced move.