Xennotoph, Reagent Overlord

Xennotoph, Reagent Overlord costs {1} less to cast for each Demon you control.
Firststrike, deathtouch, indestructible, lifelink, trample haste, reach
If a demon you control would die, return it to the battlefield at the beginning of your next upkeep.
When Xennotoph, Reagent Overlord enters the battlefield under your control, each opponent discards his or her hand. Each of your opponent's maximum hand size becomes 0.