I always viewed Sinister as Cyclops's Joker and Apocalypse as his Ra's al Ghul: Batman's two biggest enemies, one is more responsible for personal trauma, the other expands his lore and mythos and is a much bigger threat. Another example would be If Sinister is Cyke's Norman Osborn, Apocalypse is his Doctor Octopus.
But Apocalypse really is the biggest enemy of the Summers-Greys. There's an entire mythos dedicated to that, Clan Askani, Stryfe, etc and as you mentioned Sinister is often portrayed as one his henchmen.
spoilers:
Now about the game, that's what I'm hoping for to the case since we already know Scott appears in the Wolverine. |
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I can't blame them, obviously I've always read X-Men comics because of Cyclops, Jean and the lore and villains surrounding them. For me, the Summers-Greys are the protagonists of the most interesting aspects of the franchise.