Okay maybe but have you seen Jojo’s Bizarre Adventure yet? Don’t sell Dio short, he’s a freaking awesome character as well.
Honestly out of all the characters nominated here, Majora might be the most insane outside of Kefka. The guy goes from destroying a young couple's marriage and cursing a little girl's father into a monster to poisoning an entire swamp full of Deku to possessing the moon so he can cause a deadly collison course to Termina, killing everyone. When you get to see what's inside Majora's mind, it gets even more bizarre. Instead of something hellish or disturbing, you see a heavenly field of grass with a lovely tree in the middle full of strange children wearing masks. That is the exact opposite of what a player would expect from an insane almost demon-like monster such as Majora. When you talk to him, he refers to you as the bad guy and himself as the good guy and then when you finally want to battle Majora, the heavenly fields is replaced with a nightmarish battleground and the battle against Majora himself is bizarre too. Majora's Mask grows bigger with a bunch of tentacles. Then you have Majora's Incarnate who basically just dances around like he doesn't even care if you, the player, defeats him. Then he turns into the more demonic-looking Majora's Wrath where he looks like something out of a horror movie.Majora: 2/10+
Kira Yoshikage: 0/10
Seto Kaiba: 1/10
I'll admit like half my noms were for your descriptions, I love them