Forewarn

Forewarn is an ability in Polished Crystal that allows the user to identify the opponent's most powerful move when entering battle. This ends up as the move with the highest base power will be revealed to the user.

Forewarn is found on a limited number of Pokémon in Polished Crystal, including the Drowzee, Hypno, and the Vuplix evolutionary line. Having this ability can be strategic as it can provide insight allowing a user to choose a different approach or switch out if necessary! You can always switch a Pokémon with this ability in and out to gain information about the Pokémon you are facing.