Light to move after 15 discs, with 1 column already full.
Connect four within 2 of your own moves. Exactly one column starts the win; any other lets the opponent off.
What the position is about
- forcing sequence — The solution is a series of threats, each one leaving the defence a single answer.
- diagonal four — The winning line runs on a diagonal, the hardest kind to see.
Finding the way in
Find the column that creates two winning spaces at once, or forces a block that sets up your second threat.
Before you touch a piece, list every forcing move you have and every threat the opponent has; the answer is almost always on that short list.
Show the first move
Start with f1. Played out against the stiffest resistance, the whole line goes: f1 d5 f2.
Solve it and the next puzzle of the same game is one tap away. Your solved puzzles are ticked in the list, in this browser only.