Rivalryin Pokémon Polished Crystal

Rivalry is an ability that increases the power of the user's moves by 25% when attacking a Pokémon of the same gender. Conversely, it decreases the power of the user's moves by 25% when attacking a Pokémon of the opposite gender. This ability can influence battle strategies, especially in situations where gender plays a role in the matchup. It has no effect on genderless Pokémon.