Corrosion is an ability that allows the user to inflict poison on any Pokémon directly regardless of the type of the opposing Pokémon. This means the user can poison Poison and Steel-type Pokémon. However, this ability has no effect on Toxic Spikes or Pokémon with Immunity. This ability doesn't affect damaging or stat-changing moves, so Steel-types retain their immunity to damaging or stat-changing Poison-type moves. If a move is reflected by Magic Coat or Magic Bounce, the reflected move will not be able to poison Steel- or Poison-type Pokémon. This ability has no effect outside of battle.