Gix, Architect of Cruelty

Gix, Architect of Cruelty's power and toughness
are each equal to the number of creature cards in
all graveyards.
Whenever an opponent casts a spell with mana
value less than Gix's power, that player loses life
equal to that spell's mana value.
Each player who lost life this turn can't cast
nonartifact spells.