Since there's nothing posted on this, I figured I'd toss out some info about this spell. At first glance, it's not clear what this does. A proc with a 2hs attack? What's that? What it means is that it procs a damage effect that acts as though you were hitting with a 2hs weapon with a base damage of the damage listed. That's important. A proc for a few hundred points isn't a huge deal. A 2hs for a few hundred? Huge. From my tests, it appears that this damage is amplified by all the normal things that weapon damage can be amplified by (skill/level/crits/slays/etc). Yes. I said slays.
It acts very similarly to Inquisitors Judgement. It'll put a 20 counter buff on you. Difference is that unlike IJ, it doesn't have much effect when it goes off (or at least nothing I notice). No lightning flashing around. No nothing. And it doesn't proc at the same super high rate as IJ. And since it procs a melee attack, it can be completely lost in the usual spam of melee attacks you have. Because of the slower proc rate and lack of flash, it's harder to see that your damage rate is really increasing. But it is. And the proof is that if you are fighting undead, you'll occasionally see really high level slays when using this ability. Like ~100k level slays.
This ability is not so much a burst damage ability like IJ, but it will increase your damage somewhat over a few minute period of time. It refreshes every 18 minutes instead of 12, but it lasts longer when running. Just activate it when it's available and it'll give you a free increase in damage. Well worth using IMO. Oh. Since the discipline appears to be instant (it creates the buff), this doesn't block the use of other disciplines. So that's a good thing too.