In July 2017, Marvel fans at D23 (and San Diego Comic-Con a week later) were given the first glimpse of Avengers: Infinity War. At both events, a three-and-a-half-minute teaser trailer for the impending epic was played, one showing Thor and the Guardians of the Galaxy working together, Thanos' hunt for the Infinity Stones, and some cosmic action on an almost unimaginable scale. Needless to say, the reaction was electric, and details spread across the Internet like wildfire.Marvel know how to keep the fans hyped, though, and the first official trailer wasn't actually released until December. It's now been followed up by a second trailer, and by now set visits and interviews have given fans a clearer idea what to expect from Infinity War. As a result, it's possible to deduce some of the main plot threads - although some, such as the location of the Soul Stone, remain a mystery.RELATED: Avengers Theory: Thanos Needs Time Travel To Find The Soul StoneTwo trailers on, though, there are still big moments from the D23/SDCC footage yet to be officially revealed the general public. Some of them are pretty big plot points for the movie, revealing how characters meet and teasing details about the big villain. Most likely they're being held back because they don't fit in the narrative flow of the released trailers (as well as ensuring fans see real and lasting value in attending events like D23 and SDCC), but they nevertheless tell us a lot about the movie. Here's every major difference between the D23/SDCC trailer and what footage has been officially released from Avengers: Infinity War.This Page: Guardians of the Galaxy Sequences

Thor Meets The Guardians

"Who the hell are you guys?" The first Infinity War trailer closed with a disoriented Thor confronted by the Guardians of the Galaxy. Those at D23 or SDCC had already seen much more of this encounter, though.

The footage opened with the Milano flying through space - through what seemed to be the remnant of a war zone. They encountered Thor in a typically humorous, offbeat manner, when his unconscious body slammed into the Milano's windshield, causing Rocket to scream about using the wipers to "get it off." The Guardians brought Thor's body aboard for examination, learning that he was still alive; Mantis awoke the God of Thunder with a psychic prod.

This was an early tease of Thor: Ragnarok's mid-credits scene, which closed with the last surviving Asgardians confronted the Sanctuary II, Thanos's spaceship. This clearly follows on directly from that showdown - one that may have serious implications for Loki - although trailers since have been understandably more focused on the actual interaction between Thor and his cosmic friends.

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The Collector's Vault

The D23/SDCC footage promised a return to the Collector's vault - and it doesn't look as though things will go well for this particular Elder of the Universe. Gamora was shown walking through the wreckage of the museum, with all its cases blown open. This may be the aftermath of the Power Stone's destruction in Guardians of the Galaxy, although considering the Collector was in possession of the Reality Stone, it's possible Thanos has learned as much and come to claim it.

It's unclear whether this sequence comes before or after the Guardians meet Thor (and may be absent from the subsequent trailers to hide just that) but it doesn't look likely Thanos has succeeded; no footage has shown the red gem in play - it's not even visible on Thanos's Infinity Gauntlet - although Joe Russo has confirmed the Reality Stone will be featured in some way. "We do use it," he confirmed to Screen Rant, although wouldn't give any details.

Action In Edinburgh

The Infinity War trailers have only given fans a glimpse of action sequences set in Edinburgh, where the Black Order come for Vision and Scarlet Witch. What little has been shown has suggested Corvus Glaive will attempt to extract the Mind Stone from Vision's head, but that he and Proxima Midnight will be interrupted by Steve Rogers and Black Widow. However, a lot more was actually revealed at D23/SDCC.

The footage shown last year included a number of scenes of Scarlet Witch in action, using her hex powers against the Black Order. It also saw Vision in a cage, presumably designed to prevent him phase-shifting. There was later a shot of Falcon in battle against Proxima Midnight, confirming that Steve Rogers will bring his whole team with him to the UK in order to help Wanda and Vision.

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It does make sense that the Edinburgh section hasn't been a central focus. Infinity War has galaxy-spanning action, but this may be the most boutique. Sequences set in New York have a certain power for the domestic audience, and feature Iron Man, Doctor Strange, and Spider-Man to boot - 'A'-level characters whose arcs are of real interest to the fans. In contrast, Scarlet Witch, Vision, and Falcon are part of the MCU's secondary cast, sometimes acting as sidekicks, never starring in their own solo movies.

Spider-Man's Apology

Perhaps the most disturbing scene aired at SDCC and D23 was a momentary glimpse of a fallen Spider-Man, unmasked, apologizing to Tony. What is he apologizing for? How badly is he injured? That's not clear, but the trailer has teased that Spider-Man will foolishly go head-to-head with Thanos himself - and be seriously injured as a result.

While this moment hasn't been elaborated on, a lot of the Titan sequence has been elsewhere in the marketing. We've seen Team Iron Man joining up with the Guardians, Doctor Strange fighting with Star-Lord, and Tony emotional on the ground. Whatever happens, it's going to be pretty serious.

Thanos Tosses A Moon

Probably the most stunning scene in the D23/SDCC footage was Thanos tossing an entire moon at the Avengers. It was possibly the most remarkable feat seen in the MCU to date, a testament to Thanos' (or, more accurately, the Infinity Stones') raw power.

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Although the trailers have neglected this scene, it was featured in EW's cover story on Infinity War, revealing a still of the already-iconic moment. We're still waiting to see it unfold in action though, as well as learn how exactly Earth's Mightiest Heroes can survive this kind of firepower.

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All in all, none of these "missing" scenes dramatically changes our understanding of Avengers: Infinity War. Trailers, set visits and interviews have made the film's structure pretty clear, and several of these scenes link easily to what's been shown in the trailers besides. But put all together, it sets up an even more exciting prospect for the film, which is now a little over a month away.

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