Although most of the footage debuted at Comic-Con International 2014 at the Marvel booth, Marvel Studios' look back at Phase 1 and 2 of the Marvel Cinematic Universe is a great retrospective on building a universe. But -- much like the movies -- there's a pleasant surprise for those that stick around to the very end: Josh Brolin as the Mad Titan Thanos. Brolin makes an appearance as Thanos in "Guardians of the Galaxy," and while many may have seen it already (judging from the record-breaking Thursday box office numbers), it's still one of the first public looks the studio has released.

Check out the retrospective below, and be sure to stick around to the very end to see and hear Brolin's Thanos.