Maurice, the Moonbolt

Maurice, the Moonbolt gets +1/+1 for each
mana in your mana pool.
Creatures you control have "{t}: add 1 mana
of any color to your mana pool."
Whenever Maurice, the Moonbolt becomes
the target of a spell or ability an opponent
controls, add mana of any color equal to that
spell or ability's converted mana cost to your
mana pool.