Zugzwang
Zugzwang means the obligation to move is itself a disadvantage. The position would be fine if the side to move could pass, but every legal move loses something.
In puzzles, the winning move often does not check. It leaves the opponent with only moves that drop material or allow mate. The rules page explains the word, and this page is the drill.
Source database: 64,450 puzzles with this tag. This trainer: 180.
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Find the move.
By rating band
These band pages are not indexed. They keep the same theme and fix the rating range.