Mjolnir is the enchanted hammer wielded by Marvel Thor.
The Uru hammer, which grants you many of his powers and abilities, forged by Eitri and the Dwarves of Nidavellir in the heart of a dying star, is enchanted, so it can only be wielded by those who are deemed "worthy" (if purchased, only you will be able to choose who can wield it).
Mjolnir is virtually indestructible. And would repair itself if destroyed or damaged, and it will always return to your hand no matter the distance through space and time.
The God Tempest's contained inside gives it unparalleled weather manipulation, flight, energy projection sensing, absorption and redirection, dimensional travel, and it also works as an unparalleled focus for your own power, with many more abilities.