The Nebulans, also known as M Space Hunter Nebula Aliens, were a race of humanoid cockroach-like aliens and were the original creators of Gigan and Megalon. Their race went extinct during The Thousand Years War.
The Nebulans resembles humanoid cockroaches in their appearance. They have a brown exoskeleton like Terra's cockroaches but their humanoid body structure gives them a slightly muscular appearance. On some parts of their exoskeleton are hairs such as on their shoulders and forearms while some areas have spines like on their necks. They have clawed hands each have their fingers and have two-toed feet. The Nebulans also have three pairs arms: one pair being the largest which they uses the most, on their backs are another pair have claws similar to a mantis's and finally a small pair that are near the largest arms which are similar in an appearance to that of Tyranosaur's. They have large insectoid eyes and mandibles as well as having a set of antenna.
The Nebulans inhabited their home planet but soon they were involved with a great war with many other alien races known as The Thousand Year War. In the war the Nebulans joined forces with the Xilians against the Kilaaks, Simians and Millennians. At some point the Nebulans found an alien dinosaur and an alien beetle and rebuilt them into Gigan and Megalon to serve them in the war. As the Millennians are trying to fin a new home, the Nebulans deploy Megalon on a mission to hunt down their UFO, eventually resulting in him crash landing on Terra. When the war ended, the Nebulans along with the other races are wiped out as a result of their battles and as a resulted, Gigan and Megalon is freed from their control.
Tenrou Island Arc
While the Nebulans don't appear in this story arc, they are brought up in a conversation as Godzilla, Rodan and Varan explain to the Fairy Tail mages Nastu Dragneel, Lucy Heartfilia, Wendy Marvell, Happy, Carla and Panther Lily as they explain King Caesar's relationship with Megalon and reveal Megalon and Gigan's origins on Tenrou Island during the war between the Earth Defenders and Fairy Tail against Grimoire Heart and the Earth Conquerors.
Advanced Technology: The Nebualns possessed advance technology such as advanced weapons, space craft and advanced cybernetic technology which allowed them to create Gigan and Megalon.
Body Snatching: A grim ability of the Nebulans is that they are able to disguise themselves as other organism by wearing the dead bodies of other organisms.