Haven't played far yet. I've just finished the prologue, escaped from the prison (the stealthy way) and have now arrived in a small town on a river.
As Mace said, the graphics are pretty good with nice effects (high settings). However, some of the effects have a less positive effect such as Filmic Depth of Field or Depth of Field during cutscenes as the graphics/textures get constantly reloaded when the perspective changes.
Sound is nice too, albeit it sometimes is misplaced/imbalanced. One time I could hear the conversation of a group standing far away from me as if I were right beside them, next moment I could barely make out what my own character was saying.
Fighting is okay. I like the way of moving my character away and around opponents and attacking them from behind. The AI isn't very clever though. Just run away far enough from them and they'll leave you alone, giving you time to regain health and start another attack when you feel like it.
So far, the prologue and prison escape was rather straight forward and scripted. Not and open world game. But this might change later.
However, I agree again with Mace -- and judging by the comments in the gog.com forum many others -- the difficult is pretty tough. I was close to giving this game up already when I was only playing the prologue; because what is probably meant as a tutorial gives the player hardly any useful hints how to proceed in certain situations. So I got roasted by a dragon again and again until I found out by reading the comments in the gog.com forum that a certain spell helps to get through the scene.
It doesn't help either that CDProject decided to use runes only to represent the different spells and weapons. With no explanation whatsoever, the player doesn't know which spell might help him. He/she has to check the "handbook" (.pdf file) for that. Not very intuitive.
Other than that this games seems to be a real click-fest. They should've offered a special collectors edition bundled with a mouse because I'm pretty sure when I'm done with this game, mine will be completely wasted. x-D Be it in combat or the different action scenes like fleeing from a dragon and shielding someone, aiming a ballista etc., there is always a lot of mouse clicking involved- especially in the action scenes.
All in all, the game looks nice and I haven't encountered any serious bug so far. Again, I haven't played far into it yet so can't give a final comment. The above is merely my first impression.
I haven't played the first game and am usually not a fantasy RPG player (haven't played any of the Dragon Age games either). I picked The Witcher 2 up because the videos looked impressive and I was interested in the more mature feel the game has to it. And in this respect, I haven't been disappointed one small bit. The opening of the prologue, the storming of a castle, already got me impressed because it actually felt like a siege. It looked and felt huge!
I'm not exactly hooked yet. But I'm still interested how this game will go on.
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