Since the two heroes joined the Avengers, Hulk and Thor have become brothers in arms and have more often than not fought side-by-side against the forces of evil–though Marvel actually made them more than symbolic brothers bonded through combat, but literal brothers, and it did so by stretching the limits of its own established canon to its absolute limits.
Thor’s family tree has always been a bit complicated especially when it comes to the identity of his mother. Many casual Marvel fans would recognize Thor’s mother as Frigga, though that isn’t actually the case. As has been established for years in Marvel lore, Thor’s father is Odin and his mother is Gaea, goddess of the earth, though a recent development has stated that Thor’s mother is actually the cosmic entity known as the Phoenix. However, Gaea was the canonical mother of Thor when Hulk was supposedly added to the family, making their connection a bit more clear at the time while also remaining incredibly muddled and downright confusing.
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In Giant-Size Incredible Hulk #1 by Roger Stern, Zach Howard, and Cory Hamscher, Hulk encounters Earth Mother Gaea who believes the Hulk is the latest iteration of Earth’s ancient race of giants. It is revealed that giants are Gaea’s children, meaning that the Hulk is directly related to Gaea according to the supposed revelation that he is, in fact, of giant descent. Gaea describes Hulk as the newest, most perfect, and most beloved of her own children.
Whether the Hulk is actually a giant or not, the fact that Gaea recognizes him as one of her children means that he is the long lost brother of Thor. The revelation of Hulk’s supposed lineage is a truly
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