"The Thing"-Maskwood Nexus

Creatures you control are every creature type.
The same is true for creature spells you control
and creature cards you own that aren't on the
battlefield.
3, Tap: Create a 2/2 blue Shapeshifter creature
token with changeling. (It is every creature type.)
If It Takes Us Over, Then It Has No More Enemies, Nobody Left To Kill It. And Then It's Won.