A mixed bag with a few strong highlights in action and art, and some letdowns in the story and gameplay.
The concept art is, at times, magnificent. Taken directly from prints by famous etcher Gian Battista Piranesi, some of the levels are a real beauty to watch and play being convoluted, evocative and well thought. The use of light is incredibly well done, the textures are highly detailed, and the overall feeling is magnificent: long gone is the usual "already seen in another fantasy title" feeling. Kudos to the concept artists and the level designers.
Another great plus is the use of Halflife 2 engine and the extensive use of physics which translates in fun and always diverse ways of killing, bashing or simply express some retained anger. Almost everything can be destroyed, thrown or burned, giving some really exciting moments. Due to the versatility of the combat mode, you'll find yourself running straight into action with your weapon above your head, then running around kicking enemies on the back, then launching fireballs or freezing them to death. There's plenty of possibilities and the combat is often rewarding.
Another interesting thing comes directly from the HL2 engine and it's related to the characters. Playing with a sidekick is never troublesome and AI characters usually behave quite well. Which brings us to the minuses.
While the HL2 engine is used to drive the characters and their interaction, we're definitely far from the heights reached by the original HL2 both in realism and variety. The role of these characters is therefore quite marginal and add very little to the overall feeling of the game. Another bad thing is that while the original HL2 immersed the player more in the game with interactive and always ingame cutscenes, this game uses the more traditional approach of prerendered animation, which honestly doesn't live up to the rest of the game and certainly detracts atmosphere. Another minus point concerns the character models which are quite similar one to another and add very little variety to the missions. And while some of the levels are a real beauty, since this game is really a mixed bag, there are some (especially the first level in the city) which are flat and honestly boring. It's quite difficult to understand why some concept art is so brilliant while some other is below par.
Still the real problem of this game lies in the gameplay. While combat is fun, it tends to get repetitive over time and the linear story translates pretty soon in the usual "enter zone, kill everyone, find hidden treasures, optionally jump a few platforms, activate lever, enter new zone" which is a real shame since this game deserved much more.
In the end this is game is a real beauty to watch, a real fun to play in hand to hand combat, and real delusion in the storyline and the overall gameplay.