(Darkslick Slagheap isn't a spell.)

Whenever Darkslick Slagheap becomes tapped, it deals 1 damage to you.

Darkslick Slagheap is indestructible. (Destroy effects and lethal damage don't destroy it.)

, Pay 1 life, Sacrifice Darkslick Slagheap: Search your library for a Swamp or Mountain card and put it onto the battlefield, then shuffle your library.