Migdor, Wandering Geysir

Whenever Migdor becomes the target of a spell or ability an opponent controls, target land that player controls becomes a mountain and loses all other
types and abilities.

Whenever a player adds {r} to their mana pool,
Migdor gets +1/+1 until end of turn.

{r}, sacrifice a land: Migdor deals damage equal to
his power to any target.