The identity of Avenger-Prime.
It's Loki, or at least, a Loki. The suit, the Asgardian headgear, the banter with Mephisto - and the simple fact that in the 616, Loki has been pivotal to the foundation of an Avengers team on at least four occasions - all fit with it being them.- Confirmed: Avenger Prime is a Loki, with him even stating that you can't have the Avengers without a Loki bringing them together.
