Dark Messiah is an exercise is brilliant laziness. It has the makings of an A+ game but falls short of expectations.
Before proceeding with the good and the bad, let me say a few words about all the comparisons to Elder Scrolls IV: Oblivion. Namely, Dark Messiah is like Oblivion in the same way the Hitman games are like the Grand Theft Auto series. You may wander around with similar weapons and with the same general goals of causing mayhem, solving puzzles and killing people, but the similarities end there. Dark Messiah and Oblivion are two drastically different types of games, with the former being a first-person action story and the latter being a fully-blown RPG. It can be said that DM's combat is superior to Oblivion's, but then I would hope so. It's newer, has linear levels, and is 100% based around fighting; Oblivion, on the other hand, offers an immersive "do almost anything" experience and an open world. So in short, don't try and compare the two games. They fall into different genres and should not be considered similar just because both have you wielding swords, shields and magic.
Now, on to Dark Messiah.
Things begin to look fishy early on when the entire plot is revealed to you minutes into the game. Foreshadowing can be a powerful tool in the hands of a skilled writer, as it allows one to hint at things to come, building up a sense of dread that something is going to happen but leaves the faintest glimmer of hope that disaster will be averted. Also, an author may choose to use foreshadowing for misdirection, for making the reader, viewer or gamer think something is going to happen only to build up to a clever twist.
Dark Messiah does neither of those things. It almost literally begins the story by telling you how it's going to end. This doesn't have any real effect on the entertainment aspect of the game's action, but it reinforces the fact that you're just slogging through a hack-n-slash bloodbath instead of making your way through an intriguing plot.
The gameplay, while generally good, has its quirks as well. Your character (Sareth), though rendered with full-body awareness, runs with stiff arm movements that make him look like a bad robot dancer from the 1980s. It's not a game-killing issue, but it makes you wonder why the developers could not have put a little more time into the animation. Also, there are a few points in the game (normally at places that feature something you have to climb over) where Sareth gets stuck on something that should not be an obstacle. It's frustrating, especially in combat, when you have to back up and make a second attempt at scaling a platform or ledge.
On a related subject, some of the puzzles in the game are absurd nods to FPS experiences from the distant past. By that I mean you are presented with pathetic sequences where you must jump across precipitous drops, reloading save-games again and again as you try to get the timing just right. In other places you must use your "rope bow" to climb ledges, and occasionally you'll find yourself jumping from rope to rope, chain to chain, as you climb and try to find the specific path the designers have laid out. Seriously, DM is a 2006 release. Hasn't the gaming industry progressed far enough that we can eliminate the tools of artificial, time-wasting difficulty -- such as jumping puzzles -- in exchange for real gameplay?
Graphically, the game is beautiful, but once more it falls short of what it could have been. The environments and textures easily rival the best out there, but there are far too many instances of seams showing (i.e. gaps between the polygons of 3D objects). I would expect such mistakes in a budget title, but not in a huge game from Arkane Studios and Ubisoft. Did the designers somehow not notice that the top of one of their Spider Temple stairways is not connected to the corridor, or did they not care?
In the broader sense, I have had a few crashes to desktop over the course of playing, but DM seams reasonably stable outside of the in-game graphical glitches. (Belatedly, I must revise the previous statement, as the game has crashed nearly a dozen times during the final two levels. Maybe it isn't so stable, after all. . . .)
There is a class-based multiplayer component to Dark Messiah, which is cool in theory, but it sucks in practice. Unlike in the campaign, the multiplayer sound is horrendous. In melee combat especially, half of the time you can't even tell you're being hit except for your rapidly draining health meter. Archers and mages seem extremely powerful in comparison to warriors, though assassins can gain the ability to turn almost completely invisible (which is unbalanced and ridiculous in its own right).
Worst of all, the multiplayer system is powered via Steam, meaning you must install the Steam software and verify your serial number through it before you can even launch DM in multiplayer mode. This is a buggy, annoying process that no one who has paid for a game should be subjected to. To add insult to injury, once Steam is installed and DM activated thereby, you still cannot run the multiplayer game without Steam running in the background. But this is all academic, because it's hardly worth playing DM online anyway.
Despite all its faults, I cannot bring myself to say that Dark Messiah is a bad game or even a broken one. It has problems, and I think the story is a lackluster effort, but it is fun to play through once. Other makers of first-person melee games (like Bethesda) can take some lessons from the combat model Arkane Studios has created. The fights in the single-player campaign are brutal, bloody, realistic and very entertaining. Even though you pretty much know what is going to happen, there's just enough of a story to keep you going, and the cut-scenes are implemented nicely. The voice-acting is passable, and unlike some people I've found myself thoroughly amused by Xana's dialogue (you'll know what I mean if you play).
Maybe a few patches in the ensuing months will notch this game up a bit, but at the moment it is an experience that will leave you marveling at what could have been but was not. It's worth playing, but I suggest waiting for the price to drop.