Marvel's Guardians of the Galaxy vol. 3 is coming (eventually), and while doing press for his new movie Bloodshot, Guardians star Vin Diesel seemingly revealed a big detail about the threequel. Speaking to ComicBook.com's Brandon Davis, Vin Diesel said regarding Guardians of the Galaxy vol. 3, "I only have two words about that character and it is 'Alpha Groot.'" Well, that claim got Marvel fans buzzing with speculation, but it turns out that Diesel may not have been as accurate as hoped. In a more recent social media exchange, Guardians of the Galaxy trilogy director James Gunn cast serious doubt on whether Alpha Groot is really a thing:
Haha no idea. Maybe he just means the most awesome Groot ever? https://t.co/B9XiE8UupB— James Gunn (@JamesGunn) March 20, 2020
I think he was talking about what he imagined the future Groot to be (he hasn’t read the script). And, yes, they’re a different being. https://t.co/ty3vJOKTxW— James Gunn (@JamesGunn) March 20, 2020
When asked by a Marvel fan what an "Alpha Groot" even is, Gunn responded with, "Haha no idea. Maybe he just means the most awesome Groot ever?"
A second Marvel fan chimed in with the idea that "Alpha Groot" could be Diesel's term for the return of the original, fully-grown Groot from Guardians of Galaxy. Gunn used that follow-up to offer an olive branch to Vin Diesel, by claiming the actor was just speculating ("I think he was talking about what he imagined the future Groot to be,") while quickly adding the caveat, "he hasn't read the script."
The original Groot sacrificed himself to save his Guardians teammates in the final battle with Ronan the Accuser. However, Groot left behind an offspring, Baby Groot, who was the star of Guardians of the Galaxy vol. 2 (and Marvel merchandise for years to come). In the tweets above, Gunn confirmed that Baby Groot is indeed a "different being" than original Groot. However, by the time of Avengers: Infinity War Baby Groot had grown into Teenage Groot; since we know nothing about Guardians of the Galaxy vol. 3's setting, it's impossible to predict how Groot may have grown, transformed, or respawened in the time since Thanos and his army were dusted.
So far, every version of Groot that James Gunn has put onscreen has become a major hit with fans - little reason to think that's going to change in vol. 3. As for when Guardians of the Galaxy vol. 3 will arrive? Who can really say at this point...