Getting a kill when you are at critical is not easy to do on a consistent basis.
Certainly not enough critical kills to gain a meaningful health return from this Dreaded Visage trait.
This should be changed to when critical restore to full health on a kill.
That would be cool. Except that for pvp, it would turn almost every gun into Crimson.
The healing people get off of lorley alone right now is atrocious. With as much as people STILL want to complain about Wormhusk despite that, I don't think it's a good idea.
And the perk does do what it says. It does give you full health. Just doesn't give you full shield as well