Emerald Sword (3.5e Equipment)
From D&D Wiki
Emerald Sword is an Undead Dread-Sacred Power Long Sword +7. It's Emerald but it's considered adamantine.
The Emerald Sword was obtained by the Warrior of Ice after many travels in which he meets Prince Arwald and Princess Airin as well as the dragon Tharos and defeats an army of undead. He then turns the sword over to Dark Lord Akron in order to save his friends (big mistake). He later uses it to defeat Akron. It has lain unused since then.
From Luca Turilli's Emerald Sword Saga.