Re: wtf is up with vipers in the Halls of Vaught?
Here's the deal with the vipers:
We all know that poison damages over a duration. If you have 800 poison damage over 20 seconds, that's 40 Poison Damage per second. Poison damage is applied each frame, so that's actually 1.6 damage per frame for the duration of the damage.
Some monsters, like the Vipers in Halls of Vaught, add physical damage to attacks that don't normally have physical damage. In this case, we're talking about the Vipers' poison attacks. The problem is, this physical damage that's been tacked on doesn't behave like poison. Instead of spreading out the total damage like poison, the total physical damage is applied each time poison damage from the vipers is applied. This means that about 50 physical damage is applied every frame in Hell. This adds up to ~1250 damage per second. Keep in mind that it's only as low as ~1250 damage per second if the poison is applied only once. If it's applied multiple times, like when your character runs through one of the clouds, that number ramps up to at least 10k+ damage per second.
It's also easy to see why DR% is no help here, but some PDR will save you. Even with 50% DR, running through the clouds will probably kill you, because half of 10k+ damage per second is still too high. PDR is so useful here because it's actually hundreds of applications of ~50 damage, rather than one application of, say, 1000.
As far as I know, this physical damage has been tacked on to all of the Viper's poison attacks, so any of their poison attacks should easily kill you, unless you have a decently high PDR.