Yeah, with Thanos likely to be the baddie, that isn't really surprising. I remember lots of rumors about the infinity gauntlet being involved in the first film, even.
That would explain so many little things too. Like Banner grabbing the spear without realizing it. And Loki claiming he 'saw things' that made him go nuts. The Gem could have been possessing him
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We are thought, and reality, and concept, and the unimaginable
I've actually never heard of the Mind Gem. Strange. Then again I never read any of the older Thanos stories. I only know about how badass he is from the Annihilation saga.