At San Diego Comic-Con, Ryan Reynolds appeared in a grey variant of Deadpool's costume, a detail fans and commentators have flagged as a deliberate Marvel Easter egg rather than a simple costume tweak. The grey suit nods to a well-known comic-book variant of Deadpool's outfit and is being linked to wider Marvel Cinematic Universe plans, including ties to the X-Men and the upcoming Spider-Man: Brand New Day.

The specific styling choice is thought to hint at connections between Deadpool's world and these other franchises as Marvel continues to weave its mutant and Spider-Man storylines together on screen. Full details of how the suit ties into the plots of the X-Men properties and Spider-Man: Brand New Day were not confirmed in the available report, but the appearance has generated notable speculation among fans following Marvel's SDCC presence.