Kurotsuchi Mayuri - End of War

Yeah, I suspect that Aizen had Byakuya, Kenpachi, Mayuri and Retsu out of the game is that- Byakuya's Bankai is omnidirectional even if you could use his illusions on him, it'll hit Aizen anyway if he's in range; Kenpachi can adapt to combat at a heightened rate- so even if he were cast in an illusion that controls his senses- he'd come out on top- he even managed to do so even with almost his senses taken out by Tousen's Bankai; Mayuri can quickly come out with a scientific method to overcome Aizen with the right preparation, and Retsu was once the combat master of the original captain generation. The captains he does face all have conventional powers he can normally react to and that he knows that they'll hold back on for the fear of others, which three of out the four captains left out wouldn't do, especially if you push one past the breaking point.