The user lays a trap of levitating stones around the opponent's team. The trap hurts opponents that switch into battle.
In-Depth Effect:
Stealth Rock's damaging methods are rather unique. Instead of doing a set amount of damage for the amount of layers given, it instead is based on the opponent's type. The attack is a Rock Type attack so the damage is based upon the opponent's Weakness to it. For a full chart, click here
Type Effectivness
Damage
x0.25 Effective
1/32 of Max HP (3.125%)
x0.5 Effective
1/16 of Max HP (6.25%)
x1 Effective
1/8 of Max HP (12.5%)
x2 Effective
1/4 of Max HP (25%)
x4 Effective
1/2 of Max HP (50%)
This shows that Stealth Rock can easily help defeat the opponent with little effort if they use a Pokémon such as Charizard or Articuno