I was thinking about villains in RE and I really think 2 enemies working together during RE 8 or a spinoff would be interesting? (but without any sort of betrayals between them) Birkin and Wesker kind of worked like that in RE Zero. What I mean is that usually there is only one big villain and he has some henchmen to aid him but what if for some future game there is some sort of combo of bad guys and basically by the end of the game you think you killed one of them but his partner in crime shows up and assimilates his dead friend (not exactly the same way Wesker escaped death with progenitor, but maybe something like the remaining villain is able to "absorb" the skills and Memories of his dead friend) and once this second villain does that, he knows its your character who killed his friend and will proceed to create a trap to destroy the hero (leaving this plot open for RE 9 or a spinoff game). I think this would be top similar to what happened in Metal Gear Solid though, when Liquid Snake fused with Ocelot to become Liquid Ocelot... ?