"X-Men: Apocalypse" is now just under a month away from arriving in theaters -- and another potentially spoilery picture has arrived online, teasing what may be one of the film's final big reveals. The image comes from Reddit, so it's not yet known if this is a still from the film, a behind-the-scenes photo shoot or possibly from a commercial. The image depicts the team in costumes that have, for the most part, yet to be seen in any trailer and only previously appeared in a photo taken for Empire magazine.

You can see the photo below -- but be warned that it might be a spoiler.

Here's why this photo may be a spoiler: if this is indeed a still from the film itself, it shows off some costumes that have yet to play a major part in the trailers and it also reveals that Storm leaves the Horsemen and joins the X-Men by the film's end. The previous look at these costumes, which was included in Empire, noted that "[director Bryan] Singer, Storm and Mystique temporarily join Charles' gang," which implied that Storm and Mystique (along with the film's director) weren't actually team members in that team photo. But here's another photo, possibly from the movie, with Mystique and Storm standing side-by-side with the other team members.

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Additionally, so far we've only seen Mystique's costume, from the bust up, in trailers; we got a quick look at close-ups of Cyclops and Quicksilver's in a recent TV spot. The costumes predominantly featured in the trailers -- and the posters -- are the all-black armored suits that the team wears in their fight against the Horsemen of Apocalypse. Their absence from the trailers imply that these costumes aren't in the movie for very long, unless there's a whole third act battle that they're withholding from being used in promotional material. Considering how little we've seen of these individualized suits, it's likely that the team gets these costumes at the very end of the movie -- and therefore, the very end of the movie has now been revealed.

We'll find out for sure when "X-Men: Apocalypse" opens on May 27.

(via Imgur)