Groot

Groot is a member of the species called Flora colossus from Planet X (the capital of the branch worlds). Comics present multiple eras of the character: an original 1960s incarnation in which Groot arrives at Earth as an invader seeking humans to capture and study, and later reintroductions (notably around Annihilation: Conquest) that recast Groot as a noble, heroic figure who wanders the universe, meets Rocket Raccoon, and joins the Guardians of the Galaxy. Source materials note social structures on Planet X (Arbor Masters, 'Ennobled Sap-line') and offer varying origin details across different storylines.

Depicted as an extraterrestrial, sentient tree-like creature and a member of the Flora colossus. Sources describe Groot as large and arboreal in form (the species name 'Flora colossus' and repeated descriptions indicate notable size and plant morphology). Specific measurements and detailed morphology vary across appearances and are not consistently specified in the cited summaries.

Flora colossi are described as a sapient plant species whose young are taught with 'Photonic Knowledge' — the collected knowledge of the Arbor Masters absorbed through photosynthesis — indicating species-level cultural learning tied to photosynthetic processes. Groot's speech is characterized in sources as sounding like the repeated phrase 'I am Groot' due to their stiff larynxes; this is described as a perceptual limitation rather than lack of complex thought, and at least one storyline (Annihilation: Conquest) represents Groot speaking eloquently in his own language. Narrative events record feats of survival, combat, and large-scale movement (including rampages, capture, apparent destruction by termites in one plot, and later survival and captivity).