Love it, love having more cultural weapons for the Duergar. In particular love that it's a viable end-game Dwarven Waraxe, when the Rune Axe is cheap but lackluster.
My only complaint is that like every other Dwarven Waraxe, it's actually pointedly bad at dealing with the enemies you'd think it should be strong against, like the Ghaleb-Duhr, because it lacks any kind of Bludgeoning quality. It's a mining tool that struggles against living boulders - viciously inane, if you think about it.