Ku Ort, if I remember right, is one of the various spells used by The Slasher of the Veils....
Ok, back to explain how it came about that I saw these spells cast...
I was watching a YouTube video posted by a Russian player where a Gargoyle thrower and friends were taking on The Slasher of the Veils. The player making the video was outside of the rotunda and could only see the spells cast, not who (or it turns out what) was casting them... So it was the Slasher casting them after all, and I had never seen them before...
BTW, I've included the video below if you want to watch... The HD quality is excellent and I really enjoyed listening to igroglaz (known as tangar here) describe the action in Russian... Prior to listening to the video here (for the best part of an hour) I have had minimal contact with Russian speakers, and always felt like the language came across as - well (in males at least) a bit grumpy... But I have certainly changed that silly opinion after listening for a while - I found the voice (language) to be quite soothing... The Slasher, however, did not appear to be of the same opinion....