Renju VCF #4996430 (5-move VCF)
To move: Black — find the move that forces a win by fours
Winning line
L10 → L12 → L8 → L7 → K8 → J8 → J7 → I6
Why this move works
The answer is L10. A five-move VCF that drives White with forcing fours (L10→L12→L8→L7→K8→J8).
The decisive J7 makes two winning points at once; White cannot cover both, and I6 completes five.