Before you can get the hammer, you'll need all five pieces of Thor's armor first. Thor's hammer is found in a very northern part of in-game's Norway, and that's an area that isn't unlocked until much, much later. One important note: You can't actually get the Mjolnir until you finish the game due to where it is located. For those that want to play the part of the Norse god, here's what you need to do in order to nab that precious hammer and gear.
It should be of no surprise that you can get Thor's Hammer in Assassin's Creed: Valhalla given the nature of this game's setting.
You can't play a Viking game and not think about Thor at least once, so why not nab his gear while you're at it? For those diving into Assassin's Creed: Valhalla, here is how you can get not only Thor's hammer, Mjolnir but also his armor too!