Pegasus vs. the storm dragon

A piece I did for a good friend, featuring a storm dragon and a pegasus dueling in the sky. as a little bit of side story to it is in essence a mythological story behind it, describing what happens during great storms. basically when a storm happens the storm dragon descends from the sky, lightning in his maw and wings like thunder. And the pegasus, the lord of the wind rises t face him in the pillars of heaven.