Mjölnir

Mjölnir is a weapon from Norse Mythology, in Norse Mythology its wielded by Thor and it's the gods main defense against the Jötunn (giants). In Vikings Mjölnir was the first item created and its intended to be the endgame item on Vikings (most powerful). To be crafted you need one Mjölnir head and one Mjölnir handle, it can only be crafting in Nidavellir.