In battle
Sheer Force raises the base power of all moves that have a positive secondary effect by 30%, whereas the secondary effects are ignored. However, this ability is not applied to moves that have a negative effect on the user, such as recoil, two-turn moves, and stat reduction after using certain moves.
If a Pokémon with Sheer Force is holding a Life Orb and uses an attack that would be boosted by Sheer Force, then the move gains both boosts but the user does not receive the Life Orb recoil damage. The effects of Escape Button, Shell Bell, and Red Card are also negated by Sheer Force.
Outside of battle
Currently, its outside of battle effects are unknown.