At 8 feet, 3 inches tall, Thanos was made taller for his MCU appearances than he was portrayed as being in the comics. Digital Design considered having "snap" briefly pop up on screen when Thanos snapped his fingers as a reference to how the snap occurred in the Infinity Gauntlet comic.
While it is never addressed in-universe, MCU director Joe Russo confirmed Thanos was around 1000 years old in 2012's The Avengers when he first appeared in the MCU.
The answer; there isn't one. The amazing thing about the Hulk is that unlike nearly every other superhero ever created, the Hulk's strength has absolutely no upper limit. He can lift a commercial airplane – which weighs around 100 tons – when he is at his calmest; that's no problem for him.
Based on what can be deduced about his species' aging, it is possible that Groot is around 14-18 years old in The Guardians of the Galaxy Holiday Special.
While Steve Rogers gets the title of the oldest human avenger, Thor Odinson, as the mighty Asgardian God of Thunder, has a much longer life span than any of his Earth-born friends.
As Cates has pointed out on Twitter, it's important to point out that “Thanos” is still Thanos' real name, and that “Dione” was what his mother originally wanted to call him before he was born.
At full height, he can reach 23 feet tall and weigh 8,000 pounds. Thanks to his super strength and knowledge of quasi-dimensional engineering, this Guardian is a formidable adversary for any Super Villain threatening the universe.
As Bruce Banner, the character is about 5 ft 9 in (1.75 m) tall and weighs 128 lbs (58.05 kg), but when transformed into the Hulk, the character stands between 7 and 8 ft (2.13 - 2.43 m) tall and weighs between 1,040 and 1,400 lbs (471.73 - 635.02 kg).
Loki is portrayed by Tom Hiddleston in the MCU with a height of 6'2” (1.88 m). The comic book height of Loki is 6'4” (1.93 m). Loki is a fictional prince of Asgard and god of mischief in Thor, The Avengers, and the extended Marvel franchise.
In the comic books, Hulk's height varies depending on which version of himself is in control. Generally, his height lands between 7-8' tall. The most common Hulk that fans know is Savage Hulk, who is "childlike" in nature and stood at a height of 7'6".
The humanoid Venom character was created with a digital model that included rigs and simulation for the face and muscles. Venom is portrayed as being 7 feet 6 inches (229 cm) tall and weighing 500 pounds (230 kg), with a "smooth, oily, black" appearance.
Thor. Blessed with the powers and long life of a god, Thor was undoubtedly the most powerful member of the initial version of the Avengers. Not only can he fly and transport between worlds, but he was also the only one capable of taking down Thanos, even after he had assembled all six Infinity Stones.
Thor was born approximately 1500 years ago to Odin, the King of Asgard, and Frigga. He was raised on Asgard as the crown prince, alongside his brother, Loki.
Nebula is a very tall woman, and appears to be taller than Peter Quill. It is assumed Nebula is younger than Gamora based on each other's attitudes, but this has yet to be confirmed. She appears to be in her late twenties, early thirties.
Gamora is based on the character of the same name from the 2008 issue of the Guardians of the Galaxy teammates. The Peter and Gamora relationship is referred to as "Starmora". If following the actors age, Gamora is approximately thirty-five years old (in human years), but is actually twenty-five in Zehoberei years.
He has feats such as defeating Surtur (who can destroy a planet), conquering the 9 realms, and sealing away Hela. While there isn't much doubt that Thanos could beat Odin if he had all 6 stones, Odin could probably defeat Thanos if he only had one or two of them.
As mighty as they are, neither Thanos nor Superman is immortal. Both have been killed in the past, meaning neither is unbeatable. However, Thanos would need an ironclad plan to trap and defeat the Man of Steel, because if it comes down to plain old fisticuffs, Superman is definitely going to win.
He did the impossible, and the Avengers think he's got a screw loose instead of offering the hero praise for the victory. In the non-canon Marvel Comics story, despite Spider-Man winning the fight against Thanos by using the Infinity Gauntlet against him, none of his fellow Avengers remember it happening.
