Why run Skithiryx, the Blight Dragon? Other than the fact that he has a built in haste, regenerate, and immediately reduces your opponents life total down to ten, he just looks really f***ing cool.
This deck ramps mana like crazy and pumps up Skithiryx to be able to kill your opponent in one attack easily. Force them to discard whatever responses they have, and destroy anything that can stop your blight dragon from flying in for the kill. Simple as that.