Generation V
Iron Barbs
Inflicts damage to the Pokémon on contact.
Detailed Effect
Whenever a move makes contact with this Pokémon, the move's user takes 1/8 of its maximum HP in damage. This ability functions identically to Rough Skin.
Pokémon With Iron Barbs
4 canonical Pokémon forms can have this Ability.

Ferroseed
Ferrothorn
Togedemaru 
Togedemaru Totem