A living tree
Groot is an important character of the Marvel Studios’ Guardians of the Galaxy license adapted from the comic books of the same name. Groot is a member of an unknown species that are humanoid trees. He is intelligent and can speak but the only words he speaks are I am Groot”. In the first movie, he is an adult tree who works as a bounty hunter with his sidekick Rocket Raccoon. But at the end of the movie, he sacrifices himself to save his friends when their ship crashes. Rocket recovers some of his remaining twigs and grows a new groot. At the end of the movie, we see his baby version and his child version in the second movie. In Avengers Infinity War, he became a teenager.