Rig a spring on an empty square. For your next 4 turns, an enemy piece except a king that steps onto it is flung one square back toward its home rank and cannot move for 1 of their turns. A slapstick trap, not a delete.
You draft Trapdoor in Buff mode. Activated: you choose when to use it, and using it is your move for that turn.
As a attack card, it removes or detonates a piece directly.
“Mind the gap.”