Ezekiel, Cursed to Wander

When Ezekiel, Cursed to Wander enters the battlefield you may shuffle four basic Swamp or Forest cards you own from outside the game into your library. If you don't, sacrifice Ezekiel.
Landfall - Whenever a land enters the battlefield under your control, Ezekiel gets +1/+0 until end of turn.
"I cannot rest, nor can I find peace. My torment shall never end."