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Shadow's Demise
The Judge Aku can send you to the Nightmare Domain. Go through the secret door behind Maldy, deep in the Nightmare Domain. Click on the Ghost of Tyr Spirit Sword and defeat it, then report to Aku. (Gabe could send you out of the Nightmare Domain.)
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Introduction
Only Mjollnir, Thor's Hammer, can defeat the Tyr Sword and bring balance back to the Nightmare Domain.(Notice: Go through the secret door behind Maldy deep in the Nightmare Domain. Click on the Ghost of Tyr Spirit Sword and defeat it, then report to Aku.)
(If you lose Mjollnir, it will automatically return to Dwarf Ledo.)