I was messing around in Ritual SSF for a fresh start and found [[Ngamahu's Flame]]. With decent damage, 60% phys to fire conversion and 20% fire pen, it seemed like a good fit for a phys spell battlemage build. In trying to figure out how to also take advantage of the axe's 20% chance to trigger Molten Burst, I discovered that it can trigger Cast on Crit. Molten Burst doesn't take a socket so it's functionally an extra link for CoC. Triggered Blade Fall with Spell Cascade creates an expected 7.5 blades per proc, which is a reasonably good fit for having Blade Blast trigger 1/5 of the time on average. I then leveled an Inquisitor to maps, took Instruments of Virtue and Righteous Providence, equipped a Tabula and the chicken axe and the best gear and jewels I had found on the way, and...
It worked?
I'm absolutely deleting white maps and early conquerors. Blade Blast can take a moment to proc against a lone boss, but once it does, the boss dies. And that's with shit gear, incomplete tree and a five-linked axe with the wrong colors. I'm impressed, though I wonder how far it scales.
Edit: The newest PoB Community Fork version seems to have a bug related to Ngamahu's Flame; equipping it generates an error. Here's a pastebin with the axe unequipped: https://pastebin.com/H6gLzc8j
I've submitted a bug report.