I tried doing a few Uther's Tarot missions hunting for ranged weapons. Obviously all of them was Nurgle infested, and all were hunt/Assassination type. And one thing that made those missions almost impossible to beat is Apostle of Nurgle as a target. Regular Apostles are a threat, but can be dealt with. But those marked as targets gain a huge permanent HP regen. And when I am saying huge - it's on a level where a 300+ DPS weapon can't bring Apostle down because he heals faster than gun deals damage. A purple heavy flamer that has stated 1000 DPS (probably a misinformation) and deals DoT on top of it can't kill it, you need a help from sentry gun. Eviscerators, Gravguns, Plasmaguns, Heavy Bolters - all fail to kill it on it's own and require a heavy DoT or fire support from sentry gun just to beat that insane healing. And that's without him casting a healing pool on itself.