Strange axe transmog from NTCL?

Checked Google and forums, no luck: Has anyone seen a strange axe transmog banner during a NTCL clear? It didn’t actually provide a new transmog option. It may have been associated with the Cow Queen. Image of the axe was a large, full crescent blade (edge facing right), looked golden in hue with possibly runic markings.

It was definitely not Sky Splitter; handle appeared to be a wooden pole.

My initial thought was…
…but you said a banner, rather than someone wielding this, so I don’t know.
Do you have a screenshot?

I don’t, unfortunately. It popped up and disappeared so fast I barely registered it, almost buggy itself (like the “New Transmog” text only showed for less than a second). But I was also on 700-something kill spree, and my FPS were a little laggy, so I kind of chalked it up to that. A few seconds after, it registered in my mind that the weapon image wasn’t framed with an overlay the same way the transmog banners normally are.

That image looks pretty close, except the blade shape is wrong. “Crescent” was maybe a bad description. It was more like a half-moon (the back edge was straight). And I have a strong impression it was golden/yellow not silver. But it came and went so fast, who knows. When I went to the Mystic, though, I had no new (star-flagged) options.