Titan is the desolated home planet of the Titans.
Home to Titans, Titan was a rich, lush world with a royal family headed by A'Lars, who sired a son named Thanos. During this time, a Celestial named Arishem the Judge created ten Eternals and stationed them on Titan. One of these Eternals, named Eros, joined the royal family and became an adoptive brother of Thanos. However, Eros eventually abandoned Arishem's ideals and fled Titan, choosing to explore the cosmos.
Titan was plagued by overpopulation, which caused a drain on its resources and sent the Titan race hurtling towards a societal cataclysm. Thanos proposed randomly killing half the planet's population as a way to preserve their finite resources, but his plan was rejected as too extreme, and he was cast out as a madman. The predicted catastrophe then hit Titan, causing the mass extinction of most of the planet's lifeforms, with Thanos being one of the few remaining survivors.
The once green and blue world turned burnt orange and brown as the upper atmosphere was ravaged by electrical storms with the broken remains of Titan society littering its surface. Even its moon was not spared, taking on a similar appearance. On a planetary scale, Titan was left eight degrees off its axis with its gravitational pull also significantly affected. Convinced that his plan could have saved Titan, Thanos became dedicated to wiping out half of all life in the universe so as to spare other planets from suffering the fate of his own people.
In 2018, the Black Order were ordered to bring the Time and Mind Stones to Titan. Ebony Maw captured Doctor Strange and brought him aboard his Q-Ship en route to Titan. As he tried to take the Stone, he was slain by Iron Man and Spider-Man. Iron Man and Strange then seized control of the Q-Ship, which crash-landed on Titan. Before they could leave, they were then ambushed by Star-Lord, Drax the Destroyer, and Mantis, who believed they were enemies. After getting their misunderstandings out of the way, they agreed to work together to defeat Thanos and made a plan while exploring Titan.
Once Thanos arrived, he briefly explained his world's history to Doctor Strange before the Avengers and Guardians of the Galaxy engaged him. After managing to effectively stand their ground against Thanos, the arrival of Nebula distracted Thanos enough that the Avengers, Guardians, and Strange just barely managed to immobilize Thanos long enough for Mantis to subdue him with her powers before they attempted to pry off the Infinity Gauntlet. When Mantis felt that Thanos was in mourning, however, Nebula deduced that he had killed Gamora and Star-Lord attacked Thanos in a rage breaking Mantis' concentration. Having become freed from his trance, Thanos attacked the Avengers and the Guardians, knocking them down with a powerful shockwave from the Gauntlet.
Using the Power and Space Stones, Thanos ripped apart Titan's moon and sent it hurtling at his foes, effectively separating his enemies. Being the only ones to dodge the debris, Strange and Iron Man engaged Thanos individually, but Strange was briefly knocked out and Iron Man was mortally wounded, forcing Strange to barter the Time Stone in order to save Stark's life. His prize secured, Thanos departed to collect the Mind Stone.
As the Avengers and the Guardians of the Galaxy regrouped after the battle, they pondered what they would do next, only for Mantis to disintegrate suddenly. Following her, Drax the Destroyer, Star-Lord, Doctor Strange, and lastly, Spider-Man disintegrated. Only Nebula and Iron Man were spared and were left stranded.
Five years later, as a result of the Blip, Doctor Strange, Spider-Man, Star-Lord, Drax the Destroyer, and Mantis were restored to life on Titan. Strange shortly conjured a portal from Titan to the destroyed Avengers Compound on Earth so that they all could help assist in the battle taking place there.
- In the comics, Thanos' homeworld is the real-life moon of Saturn named Titan, rather than a fictional planet of the same name in another solar system.