Rudra Nam UI Nasca is the former emperor of the Sovereign Alliance of the Nasca Namrium Ulmeria Empire.
During his time with Guy Crimson, he is considered as Biseinen (Beautiful Adult Man).
In the past, he was a heroic and kind man who held ideas to construct a world free of poverty and war. He took issue with Guy's sworn duty of counterbalancing humans, crushing them whenever they get full of themselves and challenged him repeatedly to try and get him over to his line of thinking. This would in time lead to a war game where Guy leads the Demon Lords and Rudra leads the humans. He was brother in law to Veldanava, first among True Dragons, and has carried the Justice King Michael Ultimate Skill on his request for the past two millennia. The burden of suppressing this skill has weighed on him so much that it has all but destroyed him. Recognizing that Michael's absolute justice is hardly itself different from evil, he requested Damrada to find someone capable of killing him during his last lifetime. Velgrynd also seeks to kill him after he falls completely to the skill's influence, namely out of devotion to him. As Emperor he shows himself to be a cold-hearted and ruthless absolute monarch who'll use any method in order to get what he wants, namely defeating Guy. This is very likely no small part of Michael's corrupting influence.
Likely because he's seen many Demon Lords rise and fall under Guy's banner, he has a tendency to look down on everyone except Guy himself and the 4 True Dragons. He doesn't think much of Rimuru, who has been active a short 3 years at most, but he's sure he'll have to send Velgrynd to deal with Ruminas.
Rudra and Guy have been at odds with one another for well over two thousand years. He actually named Guy and befriended him over the course of their battles. They fought nearly as equals with Rudra being slightly weaker but more cunning.
He has been suppressing Justice King Michael from going out of control and has nearly reached his limit and would be unable to keep his promise with “Star King Dragon Veldanava. His original agreement with Veldanava was that he would use Ultimate Skill Justice King Michael in order to unite all humans together. But if he failed, the skill would then eliminate all intelligent beings. Veldanava recognized the self-destructive nature of intelligent beings.
His spirit now resides in a soul gem in the Divine Sword Star until it is reunited with his reincarnated body believed to be Honjou Masayuki
In his prime, Rudra was a powerful Hero with strength nearly equal to Guy Crimson. While Guy battled with his overflowing power and skills, Rudra fought him as a near equal with the pinnacle of skill and technique. His strength and skill even gave Guy problems in their first fight despite the fact that Guy was using Clairvoyance to predict his moves. Furthermore, Rudra had a clear chance of defeating Guy in their first battle had he gone all out with Justice King Michael and not named him. However, over the course of their countless battles, Guy grew stronger which resulted in him starting to slowly overpower Rudra, who resorted to pulling off small tricks every so often to force draws. Despite that the Fake Rudra who had perfectly reproduced the strength of Prime Rudra was able to fight Guy equally, despite the fact that Guy had grown stronger over time.
Even though his countless reincarnations led to him losing a lot of his holy powers and his qualification as a Hero, he managed to remain a Human Saint through the sheer force of his will.
- Armageddon (Army of Angels): Justice King Michael's special skill, which allows the user to summon and control an army of angels that will destroy everything in the world.
- Heaven's Gate: Allows the user to travel into the world of angels where the altar to pray to Veldanava lies.
- Castle Guard: An absolute barrier that is said to have the highest defensive properties of all Angel Series Ultimate Skills. It's a continuously active perfect barrier that protects Rudra from all harm. It uses the “loyalty” of his subordinates around him as energy, as such Rudra can be said to be invincible as long as he has his loyal retainers nearby. However, in exchange for its absolute defense, Rudra is unable to do anything (besides watching his surroundings) usage of other Magic and Skills is restricted as well.
- Regalia Dominion: An ability that allows Rudra to dominate and manipulate a target, allowing him to control beings as powerful as Veldora after he was weakened and restrained. Furthermore, it also has a hidden ability that allows it to dominate and manipulate the angel series' ultimate skill users.
- Scorch Dragon Velgrynd Attack Manipulation (lost after his mind broke): An ability that allowed Rudra to attack by changing the elemental properties of Velgrynd’s powers even while using Castle Guard.
Other Skills and Abilities:
Holy Barrier: A barrier that allows Rudra to cut down the stats of the targets caught in it.
Sword of Light: Rudra is able to materialize his aura as a sword of light when used by the Fake Rudra who had perfectly reproduced prime Rudra's strength it was powerful enough to cut through Velgrynd's Godspeed Saberclaw and make her feel pain even though she possesses pain nullification.
Divine Sword Summon: A ritual that summons his Divine Sword Star when he is about to fight seriously. Once initiated it cracks space-time between Rudra's hands to manifest the sword.
- Divine Sword Star: A God Class sword Rudra only brings out when fighting seriously. It's an excellent blade that chooses its owner, in terms of performance it's superior to Rimuru's katana and is powerful enough to clash against Guy's Demon Sword World, which is said to be one of the strongest swords in existence.
- God Grade Armor:
- 「Oh ho? So you came here noticing your owner was stolen? Fool. With the source of your power, your master Veldora, gone, even for a Demon Lord, you’re now just a simple monster. Coming here without a single underling, it seems you don’t possess a shred of intelligence. Make haste, and rid me of this fool!」(Rudra's Comment toward Rimuru's Naivety).
- 「No way, why? Why, did the effect of my Regalia Dominion…. my “Sovereign Rule” disappear?」
- 「Why, was Veldora defeated?!
- [Impossible, that's just impossible!
It was just a lowly Demon Lord, a puny slime! It should have become powerless, after the source of its powers, Veldora, was taken away... How, could it consume its master, and take that power for itself!! I was this close to finally achieving victory against Guy!! To get in the way of my plans... Unforgivable, you lowly Demon Lord!!」(Rudra's Reaction after Rimuru Took Back Veldora from Him).