GONNA TALK MORE EVIL OCS
I will start with her super cool sister Nyla. Nyla was very dependant on Nayuta when they were growing up, always following her lead and looking up to her as they were going through life. Their sisterly bond was strong, which is unusual for a Mudor because there isn't a whole lot of familial love and loyalty in that culture. However, that sisterly love amounted to jack shit when times got tough, and Nayuta left her poor twin sister in the dust as she beat a hasty escape from certain doom. But, rather than get burned alive, Nyla's life was spared and her memories of a past life all but erased as she was given a second chance at being a good guy under the service of the Goddess of Change. And, well, the experience has indeed changed her, and while she's just as malicious and mean as any other member of her race, she's also got a good, clear head on her shoulders - and she has no desire to go back to the way she once was.
Nayuta's mother, Dima, is an enigma as far as Mudor go. She was born to her crown, but pledged not to marry or have any children - the reason being that every other prince or princess of the family had risen up against their parent and slain them to get their crown. Husbands and wives even turned against one another, each unwilling to share the power of the throne. Many suitors came to try to change her mind the only way a Mudor can - through force. But, Dima was a powerful queen, and showed no mercy to the men and women who came knocking at her door - until one arrived that finally overpowered her, and in a desperate bid to save her own life, she agreed to wed him and bear his children. It was an unhappy marriage, for she hated and feared him with all her heart, feeling more a prisoner to him than a spouse, and when he turned tail and ran from Nyx and Cerna, she had never felt more free in her entire life, even though she thought she would die by their power. But, she escaped that day to live another day - and one day came where her shackles would return. Her husband was back and enlisting her aid in turning the heavens upside down. She felt she had no choice but to begrudgingly agree. Though the situation was grim and horrible, Dima held her head high and hoped to see the day where she could plant a dagger square into her loving husband's back.
That husband's name, by the way, is Lucine, and he's basically the leader of all the bad guys in the story, pulling every string and issuing every order from the shadows. He was a Mudor born a nobody, with no real ability to transform and no name for himself at all, but his destiny and ambition far exceeded the caste he was born to. After forcing Dima to wed him and becoming king of his race, he helped the Old Gods orchestrate their little rebellion against their creator, and while he never had a hand in any battles, he was a great ally to them and committed many deadly soldiers and weapons to their cause. Since the Mudor had Chaos's favor, and since Lucine hadn't openly denounced the gods or personally fought against them, he got through the loss of the rebellion with little more than a stern warning. But as time went on, the gods recognized what a danger he and his whole race was and sent judgment upon them in the form of Nyx, the Harbinger of Death, and Cerna, the Herald of Ruin. He managed to escape certain doom by a hair's breadth, but losing everything only caused him to realize he had nothing to lose. The gods wanted him dead and he could never rest so long as it was so. So, he decided to work to find a way to turn heaven on its head and come out on top. And he's got a lot of filthy schemes in the works. As far as personality goes, Lucine is very calm and collected, which is very unusual for someone of his race, a race known for being unhinged and untamable. This trait is partly responsible for his rise to power, along with his natural charisma and incredible intelligence. He knows how to get what he wants and he knows how to manipulate people. There's not a person in the world he can't play like a fiddle.
Next in line is a woman named Nirial Nerravine, who is second in command under Lucine and was once second in command under the gods. Once upon a time, she had Sonia's job as a Maestro, a very powerful and very respected mage, and she was very good at her job. But one day, she faked her own death in order to get out of the position and make sure no one tried looking for her, and went looking for the same "ultimate power" that had consumed Nayuta's life - Laura Lucarhest. Even though she had spent most of her life in service of the gods, she was a very ambitious person by nature and was quickly dissatisfied with taking orders from a distant god. So she decided to turn against them, and become a god herself - and make them start taking orders from her.
Now let's talk about a dragon named Ardor Sacredfire. Ardor used to be a well-respected dragon lord who had a place in heaven and served the gods faithfully - but when the rebellion of the Old Gods took place and dragons were chief among the traitors numbers, Ardor was caught between his faith in the gods and his love for his dragonkin. In the end, he chose the gods, and was instrumental in fighting back against the rebels. He mourned the loss of his kin as the traitors were all sealed away, but that anguish turned to anger and rage when the gods decided dragons were too dangerous and wanted to seal them all away indiscriminately - which meant they wanted to put him away too, even though he had been such a service to the gods and had been faithful to the end. He escaped being encased in ice along with his fellow dragonkin, only to wander the empty Void as his hatred and rage burned him from the inside. When Lucine found him, he was all too happy to help take down the gods, not caring in the slightest about whether or not it would mean his own death.
Speaking of Old Gods, here's a real kicker. The Old God of Fire, Ukrum, is a supporter of Lucine's cause, as well as an old friend of his, but the situation is a little complicated, seeing as how Ukrum is kinda permanently sealed inside Karin's sword. Lucine made a failed attempt at getting the sword and undoing the seal, but Karin and her friends proved stronger than the losers he sent after her and Ukrum stayed sealed up after all. Still, he uses what power he can muster to assist Lucine's purpose, be it misinforming Karin or simply not working with her when she needs his power.
Lastly we have Notos, the Old God who rebelled against the heavens only to double-cross her comrades at the last second when things weren't looking too good for them. It's this dick move that moved the gods to spare her from punishment, but in secret she still harbored fear that retribution was soon to come. This paranoia caused her to turn against them again at the first opportunity. She was under the impression that the gods had not forgiven her and that if she were to stay and serve them, they would seal her away - if she joined Lucine's cause, she would have a fighting chance. She stayed in the heavens a long while, feeding Lucine what information she could, but it got to be quite difficult as Aria's suspicions of Notos's activities grew. Soon enough, her cover was blown, and she was forced to hide away with Lucine and wait for the war to begin.
There are other Big Bad Dudes too in the Big Bad Dudes Crew but these are all the important (and best developed) ones so there u go