Gomoku & Renju VCF: Winning with a Continuous Four-Chase

VCF — Victory by Continuous Fours — is a forced winning sequence: every attacking move makes a "four," the opponent is forced to block it (or lose at once), and you chain those fours until you land five in a row. Because each move is forcing, the whole line can be read out in advance, which is exactly what these puzzles train.

Why a four forces a block

A "four" is four of your stones in a line with at least one open end — it threatens to make five on your next move. The opponent has to block that point or lose immediately, so a four hands you the initiative (tempo). Stringing fours together lets you keep that initiative from the first move to the win.

Building the four-chase

Make a four; after the forced block, make another four; repeat. The key is finding a stone that makes a four and, at the same time, prepares the next one. The chain ends when a four becomes a five — or reaches a shape the opponent cannot fully stop.

• First, find the winning first move — the move that makes a four.
• Treat every opponent block as forced, and read the position after it.
• Look ahead: does this four connect to a next four?
• Avoid fours that get blocked with no follow-up.

Renju's forbidden moves

Renju — unlike plain gomoku — restricts Black, the first player: a double-three (making two open threes at once), a double-four, and an overline of six or more stones are all illegal for Black. So a Black attack has to avoid them — although making exactly five always wins and is never forbidden. This constraint makes Renju VCF demand more precise reading than gomoku, where anything goes.

How to practice

On TsumeDojo the Renju VCF problems ask for the winning first move and are verified by exhaustive search, so a wrong first move really fails and the right one really wins. Working through 3-move then 5-move VCFs builds the instinct to spot the forcing four-chase at a glance.