Mumm-Ra, also known as Mumm-Ra the Ever Living, is the primary antagonist of the Thundercats franchise. He appears as a major player in the second Disney vs Non Disney Villains War.
Disney Vs Non Disney Villains - Part Two
Beginnings
Mumm-Ra was once known as Wahankh, a Priest and member of Pharoah Ramses inner council. Wahankh was the Pharoah's most trusted advisor, and was considered so close an ally that he was viewed as part of the royal family. However, Wahankh's real objective was to overthrow Ramses and install himself as the new ruler of Egypt. Unlike his rivals, Hotep and Huy, Mumm-Ra did not worship the Egyptian Gods - instead, he had been contacted by the Ancient Spirits of Evil, four ancient and powerful deities who deemed him as their 'chosen one'. The spirits had been banished to the netherworld centuries ago, and had been waiting for the right time to bring their power back into the world.
Realizing that, as a Priest, he would never have the power to launch his coup d' etat, Wahankh beseeched the spirits for the power to carry out his plans - in exchange; he would rule all of Egypt in their name. The spirits agreed, and invested Mumm-Ra with all of their power, warpng and changing his body into a weakened form, greying his skin and withering him away to nothing, rechristening him as their own champion, Mumm-Ra.
At first, he believed he had been decieved, not believing that such a frail body could grant him anymore power, but he soon discovered that not only did he posses immense magical abilities, he was now immortal. By invoking the power of the spirits with the chant "Ancient spirits of evil, transform this decayed form into Mumm-Ra the everliving!" he could also change himself into a much more powerful form.
Mumm-Ra used his new powers to change into his everliving form and cut through Ramses' army and stormed into the throne room, demanding that the Pharoah surrender to him. With little choice, Ramses agreed, and Mumm-Ra seated himself upon the throne and declared that Egypt now belonged to him. During the chaos, however, Hotep and Hut had managed to slip out of the city with the Pharoah's son, Ramses II, hoping to keep him safe and raise an army to reclaim Egypt.
Unbeknownst to Mumm-Ra, those who had banished the spirits of evil, the Oberati, had sensed their powers reborn in him. Two of their order, Oberon and Mirage, met with young Ramses and his guardians and offered to help them reclaim the throne.
Meanwhile, Mumm-Ra sought to play God. With the knowledge given to him by the spirits, he began to upgrade Egyptian architecture with technology, creating a huge structure known as the Black Pyramid and using his powers to create life - he bred entirely new species using cats, lizards, jackals and simians and forced them into his service, planning to replace his Egyptian servants with his new warriors when he had bred enough of them. His creations were little more than slaves, and followed him out of fear rather than loyalty. He came to doubt the loyalties of his two most intelligent servants, Slithe and Grune, and began to breed more unstable, bloodthirsty warriors such as Kaynar and Addicus soon after.
Realizing that Mumm-Ra would be unstoppable with such an army at his command, Mirage and Oberon acted quickly, using the small army of rebels that Hotep and Huy had managed to gather to draw Mumm-Ra's forces away from the Black Pyramid. They attacked Mumm-Ra head on and managed to subdue him in battle, reverting him to his decayed form and ultimately sealing him within the sarcophagus in his own pyramid. With the royal family reinstated, Mumm-Ra's armies went into hiding.
Mumm-Ra himself was trapped in the sarcophagus for thirty years, unable to contact the spirits or his armies. It was not until, in a fit of grief and rage, Ramses II released him from his imprisonment...
Back from the Dead - Vs Scar
After the murder of his son, Pharaoh Rameses summons Mumm-Ra to wreak havoc upon Egypt's enemies. After the Pharaoh asks for a display of power, Mumm-Ra is grievously insulted. He immediately seeks out one of the war's faction leaders, Scar. Scar, cowardly as ever, sics his hyenas upon Mumm-Ra. Mumm-Ra effortlessly defeats them, forcing Scar into the fray himself. Mumm-Ra does get blinded by Scar, but recovers quickly. As Shenzi, Banzai, and Ed abandon Scar for his failure to defeat Mumm-Ra, the mummy knocks Scar off a cliff. Mumm-Ra delivers the final coup de gras, hypnotizing the hyenas while Scar is left to burn in the remnants of Pride Rock.
Aggressive Expansion
Mumm-Ra calls together his generals - Grune, Slithe, Kaynar, and Addicus - and readies himself for the war. He sends out Grune and Slithe to wipe out Mirage, one of the villains responsible for Mumm-Ra's initially being sealed away, but the two fail in their mission.
The Acolytes
Mumm-Ra, however, meets his match, if only briefly, in the Acolytes, a group of warriors trying to steal a crystal from the Book of Omens. Odin, the de facto leader of the faction, blasts Mumm-Ra away with a powerful spell. Threatened by the Dark Dragon, Mumm-Ra transforms into a more powerful form, Mumm-Ra
Mumm-Ra transformated into his powerfull form, Mumm-Ra The EverLiving
the Everliving. This new form disarms Odin and trades blows with the Dark Dragon, eventually striking the latter with a backhanded spell. Hecate, however, calls all of the Acolytes together. With one massive attack, they overwhelm Mumm-Ra, who is then forced to transform into a bird and flies away.
Delegating
Mumm-Ra and Slithe send out Kaynar to track down Mirage. Kaynar finds Mirage in the Pridelands, though he gets into a scrap with Shere Khan. Shere Khan later turns traitor after Zira tries to kill him, alerting Mumm-Ra to Mirage's location. Mumm-Ra decides to enter the spirit realm and destroy Mirage once and for all. He orders Slithe to take out the rest of Mirage's allies; though the lizard man shows some impudence, he is eventually persuaded into the attack.
Defeat in the Spirit Realm
Mumm-Ra observes as Mirage and Zira travel in the spirit realm in hopes of defeating him. Mumm-Ra follows them into the realm and makes himself known. Zira attacks with wild slashes, slashes Mumm-Ra easily evades. Tired of toying with the lion, Mumm-Ra transforms into Mumm-Ra the Everliving once more. This new form knocks Zira off a cliff to her death. Mirage summons some fire cats to destroy Mumm-Ra, but he absorbs their energy. He then tries to annihilate Mirage, but she deflects the strike. Once again, Mirage's magic begins to banish Mumm-Ra. The mummy clings on, but soon discovers Scar, now existing in limbo in the spirit realm. The lion throws Mumm-Ra into oblivion. In the form of a bird, Mumm-Ra just manages to slip out before the portal to the spirit realm explodes.
Humbled
Drained of energy, Mumm-Ra returns to his pyramid. Rameses, however, has returned. The pharaoh wants to know who was responsible for killing his son, or he will kill Mumm-Ra in his weakened state. Mumm-Ra is only too happy to reveal Queen Grimhilde as the killer as Rameses vows vengeance.