Saike was one of the main leaders of the resistance against him. Mastering blood magic made him virtually indestructible as he always has blood to regenerate himself from. During a siege from Acroyle, he challenged Saike to a battle under any of his terms which he chose to fight him in the remains of his version of hell where he could use the most energy to try and defeat him. After a long battle Saike tired out and Acroyle forced Tekai to absorb Saike to make sure he didn't come back
Acroyle purged all hell's in Bossfights and Saike 's had his Kin which the blood element in my verse or whatever uses soul like magic and his Kin is pretty powerful I'm guessing so being in his hell with the remnants of his people would give him the most power
If you're gonna kill him off know that the only way to properly "kill" him is by throwing him into a star or something that can constantly tear him apart faster than he can regenerate
During the time Tekai tried escaping from Acroyle she ran into Gas mask and UO who were there on a siege with the rebellion. Acroyle didn't have time to deal with her and he was busy killing his son so he sent his troops to take her. Tekai entrusted them with a secret experiment she wanted them to take down for her so she basically drugged them with steroids and they were able to get through the early development troops on their own. Eventually they shut down the experiment by setting off the reactor but they were too injured to escape so they shared a drink before being evaporated
I originally had Autumn die to make Scar go berserk on Acroyle but after she obtained the Blood eye I changed it to where Scar, still went berserk and died to Acroyle which left Autumn in pieces. She joined the rebellion and is apart of Zeal's squad as second in command
Ares took him over and the rebellion killed him due to him f**king around but he transferred himself to one of Acrolye's troops and disappeared, I don't think I've got plans for him in the future lore but if you have ideas then I'd love to hear