Master of Dragons

{g},{t}: Target dragon creature you control deals
damage equal to it's power to target creature.
{r}{g}, {t}: Search your library for a dragon creature card, reveal it, put it into your hand, then shuffle
your library.
{b}{r}{g}, {t}: Create a 5/5 red and green dragon creature token with flying and trample.
Whenever you cast a dragon spell, untap Master of Dragons.