Learn How to Underpromote: Advanced Pawn Fork
This puzzle shows why a passed pawn can be stronger than it looks when it reaches the last rank with tempo. Instead of automatically choosing the most obvious promotion, the key idea is to consider whether a lesser piece creates a stronger tactical result. Here, the pawn advance does more than gain material: it also gives check and changes the balance of the position by forcing the king into a vulnerable square. That combination of promotion and initiative is a classic advanced pawn motif.