Dracolich

Dragons live a long time, but they still die. Some dragons, however, choose not to die- and use dark rituals and unholy pacts to consume themselves. They bind their souls to precious gemstones, and take on many of the properties of a lich.

Due to their innately evil nature, dracoliches tend to be of chromatic dragon stock, and look mostly like they did in life- just mouldier or skeletal. Dracoliches retain all of their living abilities (like breath weapons, flight, frightful presence, and so on) but gain all of the usual undead immunities and vulnerabilities (poison, charm, paralysis, etc.). Most DMs will also throw in the ability to control undead too; they are a Lich after all, and what self respecting undead dragon lord doesn't want an entourage of dragon guard wights?