Abilities › Dry Skin
Dry Skin — Effect & Pokémon (Pokémon Champions)
Effect: Restores the Pokémon's HP in rain or when it is hit by Water-type moves. Reduces HP in harsh sunlight, and increases the damage received from Fire-type moves.
Description text is the mainline series' official wording. Pokémon Champions generally matches this behavior, though a few details may differ.