Flash lowers the target's Accuracy by one stage.

Stats can be lowered to a minimum of -6 stages each. Pokémon with the abilities Keen Eye, Clear Body or White Smoke cannot have their accuracy reduced.

When a Pokémon is holding Normalium Z and uses its Z-Power, Flash turns into Z-Flash and raises Evasiveness one stage, in addition to its usual effect as above.

Flash lights up dark caves. In the original games dark caves made the screen almost completely black, whereas in later games you can always see a very short distance around you; Flash merely expands that circle. In the games it is an HM, it can only be used with the appropriate Gym Badge.