Stealth Rock
Stealth Rock is a move in the Pokémon games that creates a field of sharp stones around the battlefield. When an opponent switches in a Pokémon, they take damage based on their type. Specifically, Pokémon that are weak to Rock-type moves will receive more damage, while those resistant to it will take less.
This move is commonly used in competitive battles to gain an advantage by punishing opponents for switching their Pokémon. Stealth Rock is particularly effective because it can chip away at the health of multiple Pokémon over time, making it a strategic choice for many trainers.