Cavern of Souls is a mythic Land card from Magic: The Gathering (Magic Online Promos, PRM).
Mythic
Magic Online Promos (PRM)
Mana Value
0
Card Text
As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.
