Thanos (performed by Josh Brolin) is an evil alien warlord and a hidden villain in Jaden joins The Avengers. Originating from the planet Titan, Thanos, after the death of his planet, came to believe that the resources of the universe were finite. As such, he became a war-lord and set about to wipe out half of the known population of the universe. He eventually became obsessed with collecting the infinity stones in order to obtain his goals.
- Thanos will appear in Jeffrey & Friends' Storm Adventures of The Avengers.
- Thanos will appear again in Jeffrey, Jaden & Friends join the Guardians of the Galaxy.
- Thanos will appear in the post-credits scene in Jeffrey, Jaden & Friends' Storm Adventures of Avengers: Age of Ultron.
- Thanos will appear in Twilight joins the Avengers.
- Thanos will return for revenge (and face Hiccup for the first time) in Jeffrey, Jaden, Hiccup & Friends' Storm Adventures of Avengers: Infinity War.
- Thanos will return in Jeffrey, Jaden, Hiccup & Friends' Storm Adventures of Avengers: Endgame.
- Twilight nicknames him "mad titanic abomination".
- He is actually a playable character in Fortnite for some reason.