crashes randomly on singleplayer and very often on multi (doubt you will be able to finish it with whole team), there is a bug by the end of the story that softlocks you often and you either need to loose your useful items or have to start again whole thing.
the only cool things is that there are 3(?) new enemy types and that you can use Spray of Judgement magick in this (funnily enough if you use it on ghosts several times it might crash game), too bad enemies from this doesn't seem to be in challanges
and remember that this game is abandon-ware and crashes around every 30min
(base game and other stuff is still playable, even without patching at least on some PCs, but this shit is not worth buying)
IMO before they fix the fkn base game no point in buying this, PvP maps and gear packs with weapons & staves (that are only usable in challanges and PvP), not to mention fixing bugs/glitches in this DLC alone;
and if you really want to get all achievements then use steam achievement editor - me and other people bought this, you don't have to.