Thanos is the most loved and biggest villain of all time in the Marvel multiverse, people loved this character more than any other supervillain. There are more possibilities than Thanos isn’t going anywhere.
Although Thanos vanished in Avengers – endgame but MCU has their theory before the endgame which shows that the multiverse still have a seat for Thanos, he could be seen in phase four, there are some rumors that Thanos could be seen in Eternals at his young age, A’lars, his father which shows that we can see him at his young age.
He will show up in Eternals. Starlin confirms by saying,
“They made a s*** load of money off this guy. So I don’t see them retiring him anytime soon. Comic book characters tend to have an extended lifespan beyond the actors who work on them. I’m half expecting to see much more Thanos down the line.”
Eternals: Who will star?
Casting of eternals is confirmed by these actors who are
Angelina Jolie as Thena
Kumail Nanjiani as Kingo
Salma Hayek as Ajax
Richard Madden as Ikaris
Phastos, Gigamesh, Makkari, have also been cast.
Even though the whole cast is set, if Thanos would appear in Eternals it could explain some earlier theories of marvel like they’ve done in Endgame which clearly shows what happens in past was suspense at that time but make sense afterward, Eternals could show the origin of Thanos and the incomplete story of the planet “Titan”. MCU was planning to introduce him in Thor the dark world but later canceled, maybe this time Thanos’s childhood will be seen.