Let’s also not forget that the sixth Infinity Stone still hasn’t been revealed yet, so there’s a chance it could finally pop up in Thor: Ragnarok.
Regardless, with Black Panther set on Earth and dealing with the hero’s troubles in Wakanda, it’s fitting that Thor: Ragnarok will be used to lay important cosmic foundation for Avengers: Infinity War, which promises to be Marvel’s biggest event yet.
The easiest answer to this question likely lies through cosmic connections between the two movies.
Thor: Ragnarok will primarily deal with Thor battling Hela and her forces and surviving on the planet Sakaar, but once the main events have concluded, it’s possible that we could see a cameo from Thanos, who hasn’t appeared since Avengers: Age of Ultron.