The Aetherspark (231)

As long as The Aetherspark is attached to a creature, The Aetherspark can't be attacked and has "Whenever equipped creature deals combat damage during your turn, put that many loyalty counters on The Aetherspark."
: Attach The Aetherspark to up to one target creature you control. Put a +1/+1 counter on that creature.
: Draw two cards.
: Add ten mana of any one color.