Kill Celeborn.
A mithril longsword
Kill Celeborn and take the sword from his corpse.
If the unique weapon A mithril longsword is not in, then Celeborn the wise, Lord of Lothlorien will be wielding A finely crafted longsword.
A mithril longsword is a good sword, with one special feature. When you are outside, and dusk begins, the sword will begin to glow, becoming An ithildin longsword (glowing). When the night time starts the sword will increase it's glow, becoming An ithildin longsword (blazing brightly). Each level of glowing will increase the power of the sword, however it will only glow whilst you are outside.
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