Swamp Dianoga

Swampwalk
When Swamp Dianoga enters the battlefield,
target creature gets -X/-X until end of turn,
where X is the number of untapped
lands you control.
Plot {2}{b} (You may pay {2}{b} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)