David, Omega Prototype

David, Omega Prototype has the creature type
of each creature on the battlefield
David, Omega Prototype's power and toughness
are equal to the number of creature types he has.
Whenever another creature coming into play
would cause David, Omega Prototype to gain a
creature type, it's controller may draw a card
"I may not have been there for the begining,
but i will end you."