A lot. I think around 1200, though I don't know exactly. I recommend casting Demi 2 from a Time Mage, maybe some Holy, you know, anything that can deal a lot of damage to a single character very quickly, preferably at a long range. Demi 2 destroys half on an enemy's hit points, and it has about a 50% chance of working. Normally that's not a lot, unless of course you're fighting a zodiac monster, half of his hit points is half the battle.