Energy Devourer Dragonling

Indestructible, flying
{t} Add {b} or {w} to your mana pool.
{1}{t} Energy Devourer Dragonling gets +1/+0.
When Energy Devourer Dragonling has 5 or
more power, sacrifice it. When you do, create a
7/5 white black Energy Devourer Dragon
with indestructible, double strike, and "{t} Add
{w/b}{w/b}{w/b} to your mana pool."