In the final fight of the Dryford Ruins, against Wymund and his cultists, the Deep Wounds effect seems to be doing too much damage. On successful hit or graze, the Cultists apply Deep Wounds to their target, which repeatedly (and instantaneously) triggers for 13 stamina damage until the target is KO'd. Here's what the combat log looks like. This has happened consistently whenever I attempt the fight, and affects all of my party. 

 

Here's my save file from right before the fight. I've had lots of other weird behaviors as well - DT seemed abnormally high in the Dryford ruins (almost all enemies did <=1 damage on every hit, even when they outrolled my listed DT) among other issues. I did use the 'Continue' feature at some point.

I created a new character/fresh save and made my way back to Wymund and had the same issue with Deep Wounds doing extremely high amounts of damage.

Edited August 19, 201411 yr by PRETENT10uS

I've had this same issue as well. But on one occasion it went the other way and my rogue started applying ridiculous amounts of damage, just one-hitting everything basically. When that happens, though, the combat log shows it as many different attacks

Had this happen to me too.

One of the non-boss dudes one-shotted my entire party (one by one) on several re-loads.

It got to the point when I was wondering if I was underleveled of something.

 

I managed to identify and swarm the guy (after turning the difficulty to "Easy"), and win the fight.

But yes, Deep Wounds definitely seems bugged there.

Happened to me as well - the entire fight was over in about 10 seconds flat, and not in a good way