On average RDW will have to spend one mana per card which will do 2 damage (including lands that is, the spells alone have a slightly higher mana cost and average damage output but it is easier to work in whole numbers and so the inclusion of the lands makes it so near to 2 damage for 1 mana you can forget the fractions)
Card Name Mana Cost Type Creature Elemental Rarity Common rules Text Whenever you cast a noncreature spell, if at least four mana was spent to cast it, put a +1/+1 counter on this creature
The answer is, as usual, a complex one
Miku will be available on special cards in four upcoming expansion packs for Magic , each one with unique powers, special artwork, and specific themes
You'll also need Feldon of the Third Path on the battlefield, equipped with Illusionist's Bracers, and Worldgorger Dragon and Anger both in your graveyard
It is certainly a card that demands an answer, given the stream of cards that could be produced off of the top of the library