Conspiracy

As this enchantment enters, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

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}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Artificial Evolution

Change the text of target spell or permanent by replacing all instances of one creature type with another. The new creature type can't be Wall. (This effect lasts indefinitely.)

Arcane Adaptation

As this enchantment enters, choose a creature type.
Creatures you control are the chosen type in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Reaper King

({2/W} can be paid with any two mana or with {W}. This card's mana value is 10.)
Other Scarecrow creatures you control get +1/+1.
Whenever another Scarecrow you control enters, destroy target permanent.

Leyline of Transformation

If this card is in your opening hand, you may begin the game with it on the battlefield.
As this enchantment enters, choose a creature type.
Creatures you control are the chosen type in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.