I really cant remember it now, but anyway, you do get xp for giving the ancient armor to the phantom knights in firewine ruins, so i wouldnt do it. the sword is REALLY bad:
SPOILER
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- Dont have the stats here but i think its a long sword +2 which heals the opponent and damages you
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"I miss the Angel... and I mean that I REALLY miss her" -Ertai, Captive of the Blinding Angel