During one of Ark's missions, they were forced to improvise an ether-wielding edge with the assistance of other swordsmiths apparently versed in ether channeling. AuTek learned a lot from this weapon, and it's been regarded as the missing link of enchanted modern blades. Without it, learning how to apply ether-channeling to their own forged weapons technology may have remained a far-off goal.
The edge on this weapon appears to be composed of a hardened, plasma-like energy. Under examination, R&D determined the nature seems electrical in nature. As if lightning were harnessed and forged into a hard edge of ionized air.
While the weapon is not wholly understood, and some secrets kept by the assisting smithies who worked on the blade with Ark, it did not fail to yield invaluable finds.