10 MCU Theories That Come Directly From The Creators
8. Thanos' Sword Was Made By Eitri - Avengers: Endgame
One of the few distinct changes evident in Endgame's 2014 version of Thanos is that he carries around a gigantic Double-Edged Sword, which during his battle with Captain America is strong enough to slice chunks out of Cap's Vibranium shield, suggesting it's made of an unearthly, exotic metal.
On the director's commentary for Endgame, Joe Russo floats his own theory about the origins of the colossal weapon, remarking, "Well, Thanos clearly knew of Eitri."
The implication is of course that Eitri (Peter Dinklage), the King of the Dwarves who created both the Infinity Gauntlet and Thor's weapon Stormbreaker, built Thanos' huge sword.
Better still, Endgame's screenwriters Christopher Markus and Stephen McFeely quickly concurred with Russo, providing fans with an explanation that's about as canonical as they get - even if it's technically not official.