)   Mjollnir   War hammer.png
Base item war hammer
Damage vs. small 1d4+1 +1d24
Damage vs. large 1d4 +1d24
To-hit bonus +1d5
Bonus versus not shock resistant
Weapon skill hammer
Size one-handed
When carried


When wielded
  • throwable
When invoked


Cost 4000 zm
Weight 50
Material iron

Mjollnir (or Mojo) is a neutral artifact weapon. It is a reference to Mjölnir, Thor's hammer from Norse mythology. The damage of an ordinary war hammer is fairly low, which Mjollnir sadly inherits. However, Mjollnir deals an additional 1d24 lightning damage to non-shock resistant monsters; this can destroy wands and rings carried by whomever it strikes, including the player who throws it.

Mjollnir is the first artifact Valkyries receive upon sacrificing at an altar. Any neutral character may receive Mjollnir as a random sacrifice gift. If the character has strength of 25 (usually achieved by wearing gauntlets of power) and is currently wielding Mjollnir, they can throw Mjollnir at enemies like a ranged weapon. Furthermore, if the character is a Valkyrie, there is a 99% chance of Mjollnir returning[1], and a further 99% chance of catching it (this chance is reduced to zero if player is confused, stunned, blind, hallucinating, or fumbling[2]). If the thrower fails to catch the hammer, it has an equal chance of falling to their feet or striking the thrower, dealing damage as well as possibly exploding wands and rings. Note that Mjollnir can still destroy rings and wands even if the player is shock resistant. Because of this, many players choose not to throw Mjollnir, though the technique can still be employed with success by careful players.


Mjollnir does the most damage on average, unenchanted, of any artifact weapon (even two handed ones) making it an attractive choice in the early game. Very few monsters in the early game resist lightning, making Mjollnir an excellent weapon. There are a few monsters in the late game who resist lightning, the notable ones being Blue Dragons and Energy Vortexes. Basic skill in hammer is available to most classes and being neutral, Mjollnir can be wished for and used by any alignment.

Beware throwing Mjollnir at a disenchanter: Mjollnir still has a ten percent chance to be disenchanted. If a thrown Mjollnir is disenchanted, you will not receive a warning like you do for hitting a disenchanter in melee combat ("Your Mjollnir seems less effective").

Average damage calculation[]

We assume the player has expert skill in hammer, which gives a +2 damage bonus. A blessed weapon deals 1d4 extra damage against demons and undead. The worst case scenario is against a shock resistant, non-undead, non-demon large monster. The best case scenario is against a non-shock resistant, undead/demon small monster.

Weapon Against regular non-shock resistant small monsters Against regular non-shock resistant large monsters Worst case scenario Best case scenario
Uncursed Mjollnir + 0
Blessed Mjollnir +7

Encyclopedia entry[]

Forged by the dwarves Eitri and Brokk, in response to Loki's
challenge, Mjollnir is an indestructible war hammer. It has
two magical properties: when thrown it always returned to
Thor's hand; and it could be made to shrink in size until it
could fit inside Thor's shirt. Its only flaw is that it has
a short handle. The other gods judged Mjollnir the winner of
the contest because, of all the treasures created, it alone had
the power to protect them from the giants. As the legends
surrounding Mjollnir grew, it began to take on the quality of
"vigja", or consecration. Thor used it to consecrate births,
weddings, and even to raise his goats from the dead. In the
Norse mythologies Mjollnir is considered to represent Thor's
governance over the entire cycle of life - fertility, birth,
destruction, and resurrection.


Mjollnir in its present form first appeared in NetHack 3.0.3. It replaced a lucern hammer named Thunderfist, which also dealt lightning damage and appeared as early as NetHack 3.0.0. The original programmer of Thunderfist perhaps did not understand that a lucern hammer is a polearm.

The present throwing behavior (25 strength needed, returns to the hand of a Valkyrie) first appeared in NetHack 3.1.0.


Mjollnir's weak base damage is somewhat ameliorated in SLASH'EM, where it is instead a heavy hammer with base damage of 1d6 against both small and large foes. Otherwise it remains unchanged, although the different behaviour of gauntlets of power means that obtaining the strength to throw Mjollnir is more difficult than in NetHack.

Source code references[]