毁掉 is a resultative verb compound (r.v.) where 掉 acts as a result complement meaning 'off' or 'away', giving the sense of destroying something completely. You can use it with the 把 construction (把 + object + 毁掉) to emphasize the action on a specific object, or with 被 for passive voice. It works for both physical objects (buildings, documents) and abstract things (reputation, plans).