Avengers: Infinity War’s Stormbreaker could have been designed to kill Thor. Mjolnir was the Thunder God’s go-to weapon for a long time. It wasn’t until Thor: Ragnarok that he was forced to acquire Stormbreaker after the magical hammer’s destruction by Hela. Thor, on the other hand, maybe unaware that the battle-ax was specifically designed to neutralize him.
During Thor’s Infinity Saga, there were many heartbreaking events In Thor: Ragnarok. This is where he suffered the fate of Odin and the damage of Asgard, two significant setbacks. So, it’s no surprise that when he slaughtered Loki and Heimdall along with half of the remaining Asgardians at the beginning of Infinity War. He was definitely hell-bent on seeking revenge against Thanos.
The God of Thunder decided to travel to Nidavellir instead of Earth to reunite with his fellow Avengers to obtain a “Thanos-killing-kind” weapon from the master blacksmith, Eitri. Fortunately, Stormbreaker was delivered by the King of the Dwarves.
The battle-ax is a powerful weapon, as evidenced in both Avengers: Infinity War and Avengers: Endgame. To defeat Thanos in Wakanda, Thor would have simply gone for his head. However, one theory suggests that Stormbreaker was formed to kill the Asgardian Prince rather than the Asgardians. At that time, Thor had no idea the weapon existed. After Thor persuaded Eitri to help stop the Mad Titan, he brought out the mold.
Stormbreaker is “a king’s weapon, meant to be the greatest in Asgard,” according to the Dwarf King. Eitri didn’t elaborate further. Nonetheless, it’s possible that Odin was the one who had it made if Thor lost his way and became unhinged like Hela. This is so since Odin had been the Asgardian king for centuries. The erstwhile Allfather may have identified Thor’s bad inclinations. Furthermore, he may have also decided that it’s better to have a backup plan in case he follows in the footsteps of his sister after learning a challenging lesson from his firstborn. That’s not all: being named Stormbreaker, also seems like a nod to the battle-ax’s potential real-world use. This is so since Thor is known as the God of Thunder.
There’s no way to know for sure if this Avengers: Infinity War theory is true now that Odin has died. After Avengers: Infinity War, unless Eitri returns to the MCU and reveals Stormbreaker’s origin story. That person who asked Eitri to make Stormbreaker probably talked about its purpose, as the ax’s mold exists.
The Dwarf King would have known if it was intended to neutralize Thor if Odin, in fact, had ordered its creation. It’s possible that Eitri didn’t go into much detail about why he had that particular mold in the first place. In light of Odin’s recent death, Eitri didn’t want to tell Thor that his father had appointed a secret ax that was meant to be used against him.
The good news for Odin is that Thor did not follow Hela’s lead. Since Avengers: Infinity War, it’s clear that the Avenger hasn’t completely mastered the art of doing everything with the best of intentions. In Avengers: Endgame, he relinquished the Asgardian throne because he knew he wasn’t up to the challenge. In any case, Marvel Studios still has the chance to address this theory, with the God of Thunder using Stormbreaker as his main weapon.