Mantis

Nebula, Gamora's sister, mutilated repeatedly by Thanos as a punishment for losing to Gamora in combat, begins a slow turn from villain to one of the most important characters in the saga. Mantis joins the team.

How does Thanos force Strange's hand? On Titan the team nearly wins — Mantis has him sedated, Parker is pulling the Gauntlet off — until Quill learns Gamora is dead and punches him awake. Thanos then drives a piece of Stark's own armour through his abdomen and holds him there. Strange, who spent the film insisting he'd let both Stark and Parker die first, hands over the Stone.

Thanos snaps his fingers. Half of all life in the universe disintegrates. Among the dead: Bucky, Wanda, T'Challa, Groot, Drax, Mantis, Quill, Strange, Sam Wilson, Peter Parker, Hank Pym, Janet van Dyne, Hope van Dyne, Nick Fury, Maria Hill.

Guardians of the Galaxy Holiday Special (SERIES/special, 2022) — Mantis and Drax kidnap Kevin Bacon as a Christmas present for Quill. Mantis is revealed to be Quill's half-sister. Short, funny, low stakes.

Guardians of the Galaxy Vol. 3 (FILM, 2023) — Rocket's origin: created by the High Evolutionary, who tortures and discards animals in pursuit of perfection. The team destroys him and frees his experiments. The team then disbands and reforms — Rocket becomes captain with Groot, Kraglin, Cosmo, Adam Warlock, and Phyla; Quill goes to Earth to meet his grandfather; Drax and Nebula stay on Knowhere raising rescued children; Mantis leaves to travel; Gamora returns to the Ravagers.