Which level 4 monster is the best?

What are you guys talking about!? Minotaurs, Ogres, and Cruisers one-shot Vampires in one or two hits, and they won't even have time to drain anything with their weak stats and damage. Vampires are only useful for accumulating skeletons, breaking through defenses, and dealing with Utopias and Ducks without losing skeletons or other undead units. In a fight against an opponent, they get crushed by level 5 units, let alone level 6, which doesn't even pay attention to them!