Among the enormous cast of the MCU, some characters are positioned as central figures, others play key supporting roles, and others disappear into the scenery. However, the occasional hero makes their way from the sidelines or the comic relief cast into the upper echelon through sheer force of personality, even with extremely limited dialogue.
James Gunn created one of the best-loved corners of the Marvel Cinematic Universe with his Guardians of the Galaxy trilogy that is set to conclude next summer. With his brilliant oddball sensibilities and love of lesser-known characters, he elevated his unheard-of characters to the highest halls of popularity with only a few scenes.
Groot was technically created by Stan Lee, Jack Kirby, and Larry Lieber in 1960, but that iteration of the character bears little resemblance to the modern one. In Tales to Astonish #13, Groot was billed as "The Monster From Planet X". He was still depicted as a bipedal tree, but his role was as a horror antagonist. This Groot was an invasive alien who landed on Earth with little explanation to capture human beings for experimentation. In his first appearance, a human named Leslie Evans used an aggressive breed of termites to defeat Groot. This stopped his deadly invasion and seemingly killed off the character. However, like his more modern iteration, he had a way of sticking around.
Groot reappeared 16 years later, along with several other one-off Marvel monsters. He and his new allies were set against The Incredible Hulk. This iteration of the character remains a sickly monster but is revealed to have been a scientifically crafted human-tree hybrid. Hulk does what he's best known for, reducing Groot to a pile of splinters, but he survives that as well. Well-known Guardians side-character Taneleer Tivan, AKA The Collector, found what was left of the arboreal horror and took him in.
Groot lived in Collector's zoo on Earth for an unknown period. Groot later escaped and wreaked havoc alongside his fellow captives before being captured instead by superheroes. After some time in the Negative Zone, Groot was picked up by Nick Fury's Howling Commandos, a band of paranormal soldiers employed by S.H.I.E.L.D. While held by that team, Groot found himself won to their side by Gorilla-Man. Groot fought alongside the Howling Commandos against the armies of Merlin, representing the first time Groot was ever a hero.
The version of Groot most are aware of was created in 2006 by Keith Giffen and Timothy Greene II. This Groot is a Flora colossus from Planet X, a planet populated by fellow walking trees and mammals who watch over them. Unlike the previous Groot, this one began his story by setting a captured human test subject free. After that crime against his owners, the masters of Planet X exiled Groot from his home and he was left to wander the universe. Some intervening period of the large tree's life went undocumented, but at some point, he wound up captured and imprisoned by the Kree. It's unclear exactly what he was in for, but it's who he was in with that changed Groot's life forever. Groot found himself in close company with a talking raccoon named Rocket and instantly formed a lifelong friendship.
Groot and Rocket, along with Mantis and a couple of other space-faring warriors found themselves forced into military service for their captors. The Kree needed a specialist force who could take on the massive threat posed by the Phalanx. This technocratic race sought to assimilate all other planets into their dictatorial regime. As a result, the Kree recruited Peter Quill, AKA Star-Lord to lead a team of former prisoners into battle. While this team didn't operate under the title, this was Groot's first experience alongside most of his fellow Guardians of the Galaxy. The fight against the Phalanx was less of a mission and more of a military campaign, featuring a ton of extreme action setpieces and big showcase moments. Groot was destroyed in the duel, but, as always, he survived as a single twig. Rocket kept what was left of his best friend as he regrew to his full height, just like Baby Groot in the films.
The rest of Groot's story is history. He traveled with the Guardians and did battle with all manner of space horrors. He lived on the run with Rocket as a galactic outlaw. He was once captured by The Gardener, who shattered him into splinters and used them to grow an army of evil Flora colossi. He even gained the ability to speak more than his traditional catchphrase, if only for a brief time. Groot began as one of the countless monsters of the week and became one of the most beloved characters in Marvel's canon. Groot may not look like much, but the Seed of Slaughter is an unquestioned icon with even more stories to tell.