Mistveil Hollows
Land-Forest Plains (Rare)

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

When Mistveil Hollows enters the battlefield, sacrifice it unless you pay G.

W, Tap: Target blocking creature gets +0/+1 until end of turn.

2, Tap: Target land becomes a 3/3 green Snake creature until end of turn. It's still a land.

Christopher Spencer