Cavern of Souls

T, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

This land enters tapped unless you have two or more opponents. T: Add R or G.

This land enters tapped unless you have two or more opponents. T: Add B or R.

T, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

T: Add C. T, Sacrifice this land: Destroy target land.

This land enters tapped. Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target. T: Add R.

T, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

This land enters tapped unless you control two or fewer other lands. T: Add W or U.