Prevents the user from having its accuracy lowered by other Pokémon's attacks and the user ignores any positive evasion modifiers on the target. Out of battle: If the user is your lead Pokémon, wild Pokémon whose levels are 5 or more lower than the user's have their encounter rate lowered by 50%.
Hidden Power's power and type vary depending on the individual Pokemon using it, ranging between 30 and 70 power. There is no way to change a Pokemon's Hidden Power type or power, so you are stuck with what you have. Hidden Power is always a Special-based move.