You can get Op :P With Blood Aura small Mobs die instantly and when the Bigger Guys spawn and you dont move nothing happens, even when bigger Bosses spawn after it ;) Im at 400 atm. But cool :P
Yup we tried to combat this by adding the "Barbarian" enemy that would be able to reach you from larger distance and also run faster then the tick damage of the Blood Aura however the behavior was not finished in time.