The Razor's Edge
A warhammer in disguise
Looking like a random walking stick, when a qualified runepriest or runemaster weilds it aloft, a stone head froms at the end. The stone is weightless, but increases momentum as th stick is swung in attack like the inertia created by a standard stone hammer.
The hammer cannot be thrown. Once the handle leaves the runemaster’s hand, the stone returns to Ether, from where it came.