The Drule Empire was an intergalactic empire, dominated by the aliens known as Drules. The capital world was Planet Doom, originally Planet Drule.
Voltron: Defender of the Universe Continuity
At the time of the Voltron series, the Drule Empire and the Galaxy Alliance were at war. But the Drule Empire had another problem besides the war. Due to centuries if not more of wasting their planet's resources on war and a growing threat from their own sun, Planet Drule was going to explode. This led to the exploration rivalry between the Drules and the Galaxy Alliance, which only learned late in the Vehicle series of the Drules' plight. The main Drule Empire, led by Emperor Zeppo and Viceroy Throk, had a technical alliance with King Zarkon of Planet Doom, and in theory Zarkon answered to Zeppo, though Zarkon was described early in the Lion series as being a renegade of the Empire. Late in the Lion series' first season, the main Drule leadership grew tired of Zarkon conquering and looting worlds he was supposed to turn over to them, and caused him to be briefly unseated by his son Lotor. Yet for all this, the Drule leadership's backstabbing and paranoia cost them many potential worlds, including ones the Alliance flatly ceded to them. The field commanders and the leadership also frequently thwarted efforts by the troubled Drule patriot Hazar to make peace with the Alliance and more quickly find his people a replacement world. The Galaxy Alliance had problems of its own, its leadership dismissing the Drule threat until Earth itself came under attack. The war as shown in the series ended when Planet Drule finally did explode, breaking apart the empire. The crew of the Explorer Fleet, led by Commander Hawkins, fighting through last-ditch Drule Home System defenses and traps, used their ships, including the three teams of the Voltron Vehicle Force, to evacuate what people they could, including Hazar and his immediate family, who were set to become the leaders of the Free Drule people. However, Zeppo and Throk secretly planned to wait for the new Drule homeworld to be set up, then sneak in and take over once again. Whether they succeeded in this is never depicted. In the second Lion Force season of episodes, neither the forces of Planet Doom nor the Galaxy Allliance operatives make reference to any threat besides Zarkon. It is also not known how the timeline of the two series coincide, as to when the Drule homeworld's explosion occurred in relation to the temporary defeat of Planet Doom at the end of the Lion Force's first season.
Planet Doom is now the home world of the Drule Empire.
- In the original two series that Voltron DOTU were derived from, the Main Drules were known as the Galveston Empire and the forces of Planet Doom were called the Galran Empire. Being from different continuities and series, no relation existed between them, save for both being made by Toei Animation. The one and only time the two groups interacted in original animation was in the crossover special, Voltron: Fleet Of Doom.