Pride Demon

This card costs {3} less to cast if your life total is 10 or more higher than your opponents.
Trample, First strike
Possession {3}{u}{b}{b} (If you cast this card for its Possession cost, it's an Aura enchantment with enchant creature. It returns to your hand if it's not attached to a creature.)
Enchanted creature has {t} sacrifice this creature. Look at the top 10 cards of your library, put one of them into your hand and th