Green Tubes
Land-Swamp Forest (Rare)

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

Green Tubes enters the battlefield tapped unless you pay G.

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

1BB, Tap, Sacrifice Green Tubes: Target player discards a card.

Carl Briclot