These young men do not pursue any particular goals - they just love breaking things. Be it a market stall, a shop window or a skull of an unfortunate passerby - they bust it open with some dark, evil satisfaction. It is possible these poor souls did not have enough love during childhood. It is possible they express their hidden pain and anxiety, their protest against the world through hatred and acts of violence. Maybe they just do not know of any other way. It actually does not matter. What matters though, is that city guards and law enforcement are sometimes incapable of handling the situation. In this case it is our civic duty to give them a hand.
When dealing damage, Vandal forces hero to discard all dice of random stat type.