(Elfhame Tomb isn't a spell.)

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

Elfhame Tomb is indestructible. (Destroy effects and lethal damage don't destroy it.)

: Add  to your mana pool. If you played a land this turn, Add  to your mana pool instead.