Diesel has voiced the anthropomorphic tree since the character's cinematic debut in Guardians of the Galaxy, and has voiced all the differently aged Groots in each of the character's appearances since — including the character's brief cameo in Ralph Breaks the Internet.
Though only saying the words "I am Groot," (or "we are Groot," on one memorable occasion), Diesel received scripts with each utterance translated into English — scripts also given to those playing characters meant to understand his speech.
While not necessarily as action-packed as some of his Guardians co-stars roles are, Deisel's role as Groot is still important to the MCU as a whole.
Vin Diesel's MCU Payday Rumor Debunked
A claim posted to Twitter stated that Vin Diesel made a total of $54 million for playing Groot in the MCU was debunked by Guardians franchise director, James Gunn.
Simply responding, "😂 not true," Gunn shut down the claim of roughly $13 million per movie going to the actor, who only has said five separate words thus far in his various appearances.
Could Guardians 3 See a Goodbye to Groot?
After playing the character from the start, Diesel has voiced various versions of Groot, from Baby Groot to the coming "Alpha Groot" in Guardians 3.
Guardians of the Galaxy Vol. 3 hits theaters on Friday, May 5.