Avran, The Mad Vessel

Flying, Ingest
Pay 3 life: The next time you would tap a Wastes
For mana, it can produce mana of any color.
Pay 5 life: You may play one additional Wastes
this turn. (Activate this ability only once a turn.)
Pay 10 life: You may cast a spell your opponents
own in exile without paying its mana cost.