Dry Skin is an ability introduced in Generation III.
Reduces HP if it is hot. Water restores HP.
During intense sunlight, a Pokémon with this ability will lose 1/8 of its maximum HP at the end of each turn, and during rain, the Pokémon will regain 1/8 of its maximum HP at the end of each turn. The Pokémon will take 25% more damage from Fire type attack, and will regain 25% of it's maximum HP when hit with a Water type attack.