The recent speculation on the role of Pom Klementieff as Mantis was corroborated by a merchandise toy-according to a Redditor.
From user dmh2493 who posted a photo of Mantis in the Lego Set "The Avengers," the posted was branded with a "Spoiler" tag. View the photo here.
While the original poster did not recognize his post as a spoiler, it could be perceived as such in light of recent news that Pom Klementieff has been confirmed by Deadline to be in "Guardians of the Galaxy Vol.2" but her role has not been officially identified.
Yet, Deadline and almost every other movie site have pointed their fingers to Mantis. Screen Rant says the character is definitely a fitting addition to the team on the big screen.
"A telepath and a master martial artist who can locate physical weak points on opponents, Mantis takes on a special role on Peter Quill's band of antiheroes and is even part of Quill's shady plan to bring the team together. Did we mention she can even partially see the future?"
The last part of the statement is important since time-travel is integral to defeating Thanos, along with the transformation of Magus/Adam Warlock assuming the character appears in the Cinematic Universe.
Should official merchandise toys be trusted in bringing on legitimate spoilers? It has been a practice for quite some time to formulate spoilers based on toys as the official merchandise goes on sale months before the movie premiere.
Probably the most prominent example are plot rumors/spoilers that were derived from "Avengers: Age of Ultron" official Lego sets. See how they fared in this Screen Rant article.