Board Thread:Questions and Answers/@comment-69.140.66.58-20151218225802/@comment-99.250.141.46-20200516182200

Don't know, but it's made out of Soul Copper found on the eighth floor of New Aincrad. I used the game SAO Integral Factor as a reference. Play some of the game and around the eighth floor you'll see it being made by Lisbeth for Yuuki. The Obsidian Slasher and Yuuki's Blade are both appropriate names for it. Anyways, check out Sword Art Online: Integral Factor and play up to the seventh or eighth floor and you'll get to it.