Steal one the treasures of the tomb of the king under the mountain.
The Dragon Cutter.
Start at the end of Erebor: Opening Thrain's Tomb.
Head down into the tomb, then examine the carving of Thrain carefully. Once you have continued past the statue, head into the chapel. Take the dagger from the pedestal.
If the Dragon Cutter is not in (as it is unique), it will be replaced by a chalice which can be sold to any of the treasure shops dotted around Arda.
This can be done at a mud reboot as it requires no combat to quckly get a weapon to try and procure other uniques.
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