Hi everyone, many many NB's think very highly of the Veil of Blades ultimate. I have it but haven't used it much. Sort of confused on how to use it.

I use the other two ultimates, Soul Harvest and Soul Tether, more often since they just deal damage and are easy to understand. After casting those, I keep on dealing damage until all the mobs are dead (or I die).

So what do I do after casting Veil of Blades? Do I keep on dealing damage? Run away? Stop and admire the scene? And why is Veil of Blades better than the other two ultimates?
Thanks for your help!