Hand Control allows you to target an opponent's monster, and then choose one of two effects: either the target monster is destroyed or the target monster has its ATK reduced to zero until the end of your opponent's next turn.
Hand Control is a versatile card that can be used to weaken your opponent's monsters or to remove them from the field entirely. It is a great card to use in combination with other cards that affect the opponent's hand or field, such as Mystical Space Typhoon or Heavy Storm.