- There is a Chitauri in The Collector's collection
- Cosmo is in the collection. He looks exactly as he does in the comics
- We see a full Celestial at one point
- We see the origin of the Infinity gems and we see some brief visuals of their later appearances as the Aether and the Tesseract, none of the current forms of the others though.
- Nathan Fillion is the giant brute that gets his nostrils violated by Groot in prison
- There is a Kree ambassador that briefly appears that is played by Tomas Arana
- Christopher Fairbank, the kooky scientist from The Fifth Element who rebuilds Leeloo's body has a featured role in the film.
- Ronan's minions are not Kree but actually Sakaarans. Their ships are called Necrocrafts.
- Peter Serafinowicz, longtime character actor from Shaun of the Dead, Look Around You, Spaced, voice of Darth Maul in Star Wars, plays Garthan Saal, previously Nova Omega in the comics.