DKS contains the add-on Flames of Vengeance. In terms of things remastered or changed in the D2:ED section of DKS since the original release, there were quite a few (mostly) small changes to skills, enchantments, loot, etc, more set and unique equipment was added to the game (and the D2:ED sets moved), stat requirements for equipment were removed, changes were made to enemies and their placement, boosts to some quest and enemy experience (particularly to help levelling early in the game and at the start of the fjords, to address difficulty spikes some people had trouble with entering the main part of Broken Valley and starting on the flying fortresses in the fjords). In DKS / D2:DC magic damage bonuses from equipment are added to spell damage, so mages should duel wield weapons with magic damage bonuses/enchantments, and Magic Missile is even more effective. The level dependence of combat was reduced, so opponents more than a few levels above you would not be impossible, and opponents more than a few levels below could still be a bit of a threat in groups. The flying fortresses were also redesigned (to make them more fortressy) and all but one of the anti-dragon shields and generators were removed.