Generation Ix
Protosynthesis
Boosts the Pokémon's most proficient stat in harsh sunlight or if the Pokémon is holding Booster Energy.
Detailed Effect
Boosts the Pokémon’s most proficient stat in harsh sunlight or if the Pokémon is holding Booster Energy.
Pokémon With Protosynthesis
10 canonical Pokémon forms can have this Ability.

Great Tusk 

Scream Tail
Brute Bonnet
Flutter Mane
Slither Wing
Sandy Shocks 
Roaring Moon
Walking Wake 
Gouging Fire
Raging Bolt