In his journey, both he and his Black Order invaded Xandar, Earth, and Knowhere and even murdered Loki, along with half of the surviving Asgardians, and even his beloved Gamora. Thanos engaged in a ferocious warpath in order to obtain all of the Infinity Stones.
Fed up with all the failures of his subordinates, Thanos had opted to seek out the location of the Infinity Stones himself. Both of the new alliances had cost Thanos much of his resources, including one of the stones and the loyalty of his daughters, Gamora and Nebula, and inadvertently resulted in the formation of the Avengers and the Guardians of the Galaxy. He spent many years hunting down these stones and his desire to achieve his ultimate goal is what led Thanos to forge new alliances with Loki and Ronan the Accuser in their respective campaigns against Earth and Xandar, as seen in his promising to aid them in exchange for an Infinity Stone. However, his methodology to succeed was warped through using the Infinity Stones, Thanos intended to harness their power to exterminate half of life in the universe. His own main objective was to bring stability from the universe, as he believed its massive population would inevitably use up the universe's entire resources and condemn it. Thanos is a powerful Titan warlord who rules over a distant region of space and commands two massive armies, known as the Chitauri and the Outriders, and a small group of followers known as the Black Order ( Corvus Glaive, Proxima Midnight, Cull Obsidian, and Ebony Maw). Marvel Cinematic Universe (Earth-199999) " I am.inevitable! " ―Thanos He is one of the Avengers' most historical foes, but when he took a break from being a conqueror, Thanos was entrusted with the Reality Gem of the Infinity Gems. He later became the master of the Infinity Gauntlet, which he used to murder half of the universe's inhabitants in an attempt to impress Death. Much of Thanos' villainous motivations in the comics revolve around his romantic feelings for the entity Death. Thanos himself was the son of Mentor, the leader of an Eternal colony on Saturn's moon of Titan. Thanos was a member of the Eternals, a race of superpowered beings that descended from a caste of humans genetically enhanced by the Celestials.