Four hints in the Marvel movie. The Avengers 1 has already hinted that Thanos wants to eliminate half of life in the universe

Although Thanos officially debuted in "Avengers 3", but in fact Thanos appeared for the first time in the Easter eggs of "Avengers 1," and Thanos learned that Rocky had failed. , Didn't feel unhappy at all, on the contrary came a wicked smile, which made people feel a little creepy.

should be the biggest easter egg in the history of the Marvel Cinematic Universe. From "Reunion 1", it implies that Thanos will be the ultimate villain in the future. In addition, in the scene of Thanos’ evil smile, we find that there is another Destroying half of the planet is actually implying that Thanos will destroy half of the life in the universe in the future, and I have to admire the details of Marvel.