It’s no secret that for Marvel’s main cast of cosmic characters, Avengers: Infinity War will be set four years after the events of their last outing, Guardians of the Galaxy 2. The movie in which Star-Lord, Gamora, Drax, Rocket, Groot, Yondu, and Mantis faced off with Peter Quill’s dad, Ego the Living Planet, took place just a few months after the original Guardians of the Galaxy, which was set in 2014.

That begs the question: How have Star-Lord and his crew changed in the four year gap between Guardians 2 and Infinity War? It’s easy to glean a couple of superficial changes from Infinity War‘s trailers, including Quill’s angular new facial hair, the Guardians’ new ship, and the growth that Groot has naturally experienced. Luckily, GameSpot got to pose the question to Infinity War’s writers and directors to find out more.

The main change for the Guardians, it seems, will indeed be Groot. “Groot is bigger,” said Infinity War co-writer Stephen McFeely. He added that the rest of the crew may find it easier to communicate with the living tree: “They all seem to speak Groot.”

“This is a new iteration of Groot, so there was also a process of finding what this voice of Groot is,” said Infinity War co-director Anthony Russo.

“Yeah, his behavior’s very different than in other movies,” added his brother and directing partner, Joe Russo. “He’s a bit of a dick.”

They said Vin Diesel, who voices Groot, likes to do plenty of different takes for each reading of the character’s singular line, “I am Groot.”

Other than Groot hitting puberty, the directors and writers all agreed that we won’t notice too many other big changes for the Guardians of the Galaxy. And there’s a reason for that, according to Anthony Russo: “We don’t like big story points to happen between the movies. If there’s any big story point, we want it to happen within the parameter of the movie.”

“Things have moved on a bit, but you don’t want to move on so much that you seem like you don’t know what characters you’re writing,” said Infinity War‘s other co-writer, Chris Markus. “You know, like, ‘Now Quill is very sober and serious. The years have taken their toll on him.'” He said they tried not to think about the four-year gap while they were writing.

“I think it’s just a continuation of their story,” said Joe Russo. “Obviously, they’ve been working together for four years, so they’re a lot more gelled.”

“They have chemistry, and they’ve always had chemistry,” McFeely added. “[But] nobody has a four-year-old.”

Avengers: Infinity War hits theaters this Friday, April 27. Read our spoiler-free Infinity War review, find out the best order to catch up on the MCU, and check out the 10 things we want from Infinity War while you’re here.