Rock, Paper, Shotgun's Rich Stanton has penned a Dark Souls II hands-on preview based on his time with the game at Eurogamer Expo, and decided to mostly focus on the combat system changes and what they likely mean for the multiplayer side of the game. Here's a snippet:
Parries are the core element of combat in the Souls series; they're both what let you get through a tough defense, and turn outright aggression back on itself. They worked beautifully in Dark Souls' singleplayer because they were instantaneous, split-second in both judgement and execution. You saw the attack coming in, parried the second before it hit, and boom success. In Dark Souls II the wind-up on your attacks feels considerably longer, the same goes for most enemy attacks, and in-keeping with this the timing of parries has been altered considerably. It's no longer enough to have reflexes you have to judge the attack, allow for your parry's startup animation, and combine the two.
In one sense this is simply a question of re-learning your timings something that it wasn't possible for me to do very well over the course of a demo, but will come easily enough once the game's out. The underlying question though is why make this change to such a great combat system? The answer is in Dark Souls PvP or, to be more precise, the parts of it that never really worked. To call parrying in Dark Souls PvP a hit-and-miss affair is being too kind. It doesn't work. You can parry in PvP, but the latency in the game's networking system means you can only do it reliably through prediction learning katana swing timings, for example, and gambling that an unskilled opponent will spam the attack key.
By making attack wind-ups larger, and parrying less of a twitch skill, From Software has created a way in which parries can become a core part of skill-based PvP combat rather than a high-risk roulette. And that's not all. Another change is to the hitboxes on backstabs which, in the first game, were enormous being slightly behind someone's arm was basically enough, which was eminently exploitable online and could even be combined with dodging for some true bullshit in the form of the '˜roll BS' tactic. In Dark Souls II the backstab hitboxes have been enormously reduced, so that you have to be basically facing between an opponent's shoulderblades when hitting attack. The fact that there are now bespoke animations for each weapon's backstab, and they all look amazing, is merely the icing on the cake.