Marvel insider Daniel Richtman revealed on his Patreon that Marvel is planning the “next saga” around Mr. Sinister and Apocalypse. Richtman explained, "I hear once more Marvel's main plans for [the] next saga are for Mr. Sinister and Apocalypse." Apocalypse already made his big-screen appearance in Fox’s X-Men: Apocalypse, but his MCU introduction would mark a fresh start and a chance to reimagine him as one of Marvel’s most dangerous threats. While it’s worth remembering that Marvel’s long-term plans often shift, the idea of Mr. Sinister and Apocalypse stepping into the MCU spotlight is an exciting one. For now, fans will have to wait and see how Marvel rolls out its X-Men plans.