Lava Titan

Landmorph {4}{r} (You may play this card face down as a land with "{t} : Add {r} to your mana pool." Turn it face up any time for its Landmorph cost.)
Lavatouch (This creature has deathtouch. Whenever a creature dealt damage by this creature this turn dies, add {r} to your manapool.)
At the beginning of your next turn, turn Lava Titan face down.