Draconic Swarm

At the beginning of your upkeep, put a Swarm
counter on Draconic Swarm for the amount of
dragons you control.
Remove X Swarm counters from Draconic
Swarm: You may cast Dragon, Drakon or Wyvern
creature with converted mana cost X or less. It
gains haste. If X is 12 or more, it cannot be
countered.
This is doom at it very finest.