Forewarn (よちむ Prophetic Dream) is an ability that was introduced in Generation IV.
Effects
Effects in Battle
Forewarn reveals your opponent's move with the highest base power. If there is a tie, one is chosen at random. If the user is facing two opponents, one move in all will be revealed, and it will be the move with the highest base power. Again, if there is a tie, one is chosen at random. In Mystery Dungeon 2, Forewarn occasionally allows the user to dodge a move, even moves that never miss.
Effects Out of Battle
There is no effect out of battle.