Even if it's astral damage, it can't kill much. 80 cursed ghosts (which karador had on impossible) x 60 HP is 4800 hp.
It may actually be an interesting test to stack up on mana, intellect and rage and try to do a 2x armageddon + Black hole combo, but I doubt that a mage can get enough rage to cast a decent black hole anyway.
__________________
|