Mjolnir

Mjolnir is specially enchanted to prevent it from being wielded by anyone save those who have been found worthy and possess superhuman strength. Thus far, this includes Thor, Odin, Tiwaz, Red Norvell, and Beta Ray Bill. Those who are worthy enough are empowered with Thor's essence held within Mjolnir to gain the powers of Thor. However, in times of need, Thor can will others to lift Mjolnir and overcome this enchantment, allowing them to lift the hammer. Thus far, this includes Steve Rogers, Eric Masterson, and a red and blue costumed adventurer from another universe. While holding Mjolnir together, Thor can empower others with his essence to gain the powers of Thor. Thus far, Eric Masterson has been the only one to receive this enchantment. To anyone else, Mjolnir cannot be lifted from the ground nor wrested from Thor’s grip. This enchantment does not affect non-sentient beings (such as robot drones), but even non-sentient forces must possess some level of superhuman strength to lift Mjolnir. However, without the presence of gravity, anyone can overcome this enchantment and lift, or more accurately “push,” and hold Mjolnir, but can not access or use the enchantments within the hammer.

Wielding Mjolnir, Thor can summon and control the powers of the storm, causing rain, wind, thunder and lightning. Thor can channel the storm’s fury into devastating energy blasts that can destroy even secondary Adamantium. Mjolnir can also generate energy blasts called “Anti-Force.” Due to its uru metal composite, Mjolnir can absorb other energies into itself, which Thor can then release.

Mjolnir can also transform Thor into his civilian guise as Donald Blake by striking the hammer against the ground once. When Thor becomes Blake, and vise-versa, Thor is sent into the limbo-like dimension known as the Void. Mjolnir assumes the appearance of an old wooden cane and in this form Mjolnir can be lifted by anyone. Mjolnir’s enchantments usually restore Thor to Blake’s form if he is separated from the hammer for more than 60 seconds.

More on Marvel.com: http://marvel.com/universe/Thor_complete_powers#ixzz3STTa5WGN

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