Ixs, the Living Continent

Shroud
Ixs, the Living Continent enters the battlefield
tapped.
If you control any lands other than swamps
sacrifice Ixs, the Living Continent.
You may play Ixs, the Living Continent from
your graveyard.
When you tap this land for mana all creatures get
-1/-1 until the end of turn.
{t}: Add {b} for each swamp you control.