Black Sludge

An item to be held by a Pokémon. When held by a Poison-type Pokémon in battle, 6.25% of the holder's HP is restored at the end of each turn. When held by a Non-Poison-type Pokémon, it inflicts 12.5% of damage at the end of each turn. Pokémon with the ability Magic Guard are immune to this effect.