Proxima Midnight is a prominent supervillain in Marvel Comics, created by writer Jonathan Hickman. She made her debut in New Avengers #8 (September 2013), with a brief cameo, followed by a full appearance and naming in Infinity #1 later that year. As a core member of Thanos's Black Order, an elite cadre of lethal operatives, Proxima rose from service in his Butcher Squadron to become one of his most trusted and ruthless generals. Her origins remain largely undisclosed, but she is depicted as an alien warrior of unparalleled skill and loyalty to the Mad Titan, often invoking his name in battle.

Proxima possesses superhuman strength, durability, speed, stamina, and nigh-invulnerability, enabling her to withstand extreme punishment and overpower formidable opponents such as Luke Cage and the Hulk. She is a master combatant, proficient in all forms of warfare, with exceptional expertise in thrown weapons. Her primary armament is a unique spear forged by Thanos from a sun trapped in distorted space-time; this weapon never misses its target, travels as beams of light, delivers lethal toxins, manipulates energy and mass, and can transform into a supernova or black hole under certain conditions. Proxima is married to fellow Black Order member Corvus Glaive, with whom she frequently collaborates in combat and conquests.

Proxima has featured in several major storylines, most notably the 2013 Infinity event, where she led portions of the Black Order's invasion of Earth, devastated Wakanda in search of an Infinity Gem, and was ultimately imprisoned in living amber by Thane, Thanos's hidden son. Freed later, she joined the Cabal during the incursion crisis, survived the multiverse's destruction, and emerged on Battleworld in Secret Wars (2015). In subsequent arcs, including Unworthy Thor, she allied temporarily with Thanos and Hela in a failed attempt to claim an alternate Mjolnir, resulting in her death. Revived by the Challenger during the "No Surrender" storyline, Proxima rejoined reformed iterations of the Black Order, continuing her role as a persistent cosmic threat across various conflicts.