(Sunken of the Burnwillows isn't a spell.)

At the beginning of your end step, if you didn't cast any spells this turn, Sunken of the Burnwillows deals 1 damage to you.

, : You may put a land card from your hand onto the battlefield.

, Pay 1 life, Sacrifice Sunken of the Burnwillows: Search your library for a Island or Mountain card and put it onto the battlefield, then shuffle your library.