Renju VCF #4996427 (5-move VCF)
To move: Black — find the move that forces a win by fours
Winning line
G8 → H7 → D8 → E8 → J8 → I8 → L6 → M5
Why this move works
The answer is G8. From here you chain forcing fours over five attacking moves (G8→H7→D8→E8→J8→I8), each four forcing White's reply.
Finally L6 makes two winning points at once; White cannot stop both, and M5 completes five. Even in a long VCF, every move must give a four to keep White on the defensive.