No, any XBox 360 version is backwards compatible with XBox One (including retail/disc). All versions can get the 4K update too for XBoxOneX. None whatsoever. Revolver is a very different game, much more arcade-like and less story driven. You can skip it and not miss anything story wise. The references to it aren't much more than a single conversation in RDR2, and that's more of an Easter egg for fans. Trivia time: did you know that Red Dead Revolver actually started life as a Capcom-published project developed by Angel Studios, and a spiritual sequel to the arcade and NES game Gun.Smoke? The project wasn't going well, and Rockstar bought the team doing it, and it survived as Rockstar management liked the look of it.