Mystic Lowlands
Land-Plains Island (Rare)

(Tap: Add W or U to your mana pool.)

Mystic Lowlands enters the battlefield tapped unless you control five or more multicolored permanents.

1, Tap: Target land becomes a 2/2 blue Illusion Merfolk creature until end of turn. It's still a land.

W, Tap, Sacrifice Mystic Lowlands: Prevent all combat damage that would be dealt this turn.

Justin Chippy