Greatswords of Legend: The thirty five swords were all made for noble families and holy orders. Each took a year to craft and nothing could break them -making them potent bringers of destruction against any doors, walls, or constructs reinforced or made through magic.
It shares all properties of silver weapons. As such, the weapons made from this metal were highly inimical to undead and animations as well as constructs.
Greeniron RemnantsSundered Blades: When the Sundering happened in CY 5000, every one of the blades broke, wherever it was. No common explanation has ever been provided for why this happened. After which, the pieces of the blades became workable by others, and several notable swords of the realms were re-forged or crafted from their remains – though never quite as a full great sword ever again.
The Gathering of Shards: A great deal of the shards were gathered and forged into smaller swords when the Wraith Plague happened almost 500 years later. Forged under the vision of and collection by the Druids of the Wyld and with the prowess and strength of smiths using the sacred forges of Ikribu, these slim blades were buried in the Wraithlands to anchor the magics that keep the Barrow Wraiths asleep and contained. The blades made from the remnants of Greeniron to kill them hold the power of their grave chill at bay and do not trigger it. They do maximum damage against these wraiths. They draw upon the anima powers that channel both Chi and Synergy.
All attempts by treasure hunters to try and unearth them for their own selfish desires have resulted in their deaths over the ages.