The double threat

Most short wins in board games come from the same simple fact: an opponent can answer one threat per move. Create two with one move and something falls. This guide shows how that idea looks in four very different games.

Why two is enough

A threat is a move that will win something next turn unless it is stopped: a mill, a line of four, a capture. A careful opponent blocks it. If a single move of yours creates two threats that cannot both be stopped with one reply, the opponent has to choose which loss to accept.

That means the real work happens one move earlier. You are not looking for the winning move itself; you are looking for the move that leaves two winning moves behind it.

Mill: the fork on two lines

In mill, a point where two of your potential mills cross is gold. If you already have one man on each of two lines that meet at an empty point, placing a man there threatens to complete both. In the sliding phase, a man that can step into either of two lines does the same.

The defence is to break up such crossings early: when you see two of the opponent's lines meeting, put a man on the crossing point yourself.

Four in a Row: two spaces at once

In this game a threat is a hole where your next disc would complete four. A double threat means two such holes side by side on one row, or one directly above the other, so that the block on the lower hole gives you the upper one.

Stacked threats are the most powerful weapon in the game. They are also the reason why you should never fill the space directly under the opponent's threat.

Five in a Row: four plus four, four plus three

A four must be answered at once. An open three must be answered before it becomes an open four. Combine them, a four and an open three, or two fours with one stone, and the defence runs out of moves.

The forcing chains in the puzzles work this way: each four drags the defender's stone to a known point, and the last four arrives together with a second threat.

Draughts: two pieces under attack

In draughts the double threat often comes from compulsory capture. You give one man away; the opponent must take it, and their capturing piece lands where your next jump takes two. A king that attacks two loose men at once is the same idea in the ending.

Before every move, ask: after this, how many things am I threatening, and how many can the opponent fix with one move?

Practising it

The easy puzzles on this site are mostly double threats in two moves. Solve a handful in each game and the pattern starts to jump out at you during real play.