How did Vin Diesel voice Baby Groot in Guardians of the Galaxy 2?

Action star Vin Diesel says voicing Groot in Guardians of the Galaxy is very challenging as the limited vocabulary makes it hard to get emotion across.

The 49-year-old actor’s character in the Marvel Comics movie franchise is a tree-like humanoid named Groot who can only say “I am Groot” only in that order, reported Contactmusic.

“It’s very, very challenging because you’re limited to three words. There’s a secret script that I get where it has all of Groot’s lines, but the catch of it all is the only words I can say it is: ‘I am Groot’,” Diesel says.

Diesel says voicing Baby Groot in the second film was an even bigger challenge. At the end of the first movie, Groot sacrifices himself and is reborn as a miniature version of himself.

“I have a feeling they’ll do a combination of things (to alter the sound electronically). I mean, I do it super high-pitched,” Diesel says.