What Darksiders lacks in originality it makes up for in solid execution.
Cons: Story and characters suck; Does really nothing truly original; Fairly easy; Pacing falters towards the end of the game; No real settings tweaks on the PC version
Putting out a new IP can be a little risky. If you spend a ton of money on a brand that no one has ever heard of, you want it to be a surefire success so that you get a good return. That means risks are out. A new IP should be based around tried-and-true concepts to ensure the best chance of success. It's a business mentality that I get (although disagree with), but this is a little ridiculous.
It's hard to find anything truly original about Darksiders. The core game is a mix of Zelda-style dungeon solving and God of War combat. At a couple times the game gives you a gun and plays like a third-person shooter starring the Heavy from Team Fortress 2. Another point has you flying through the air and plays like an aerial combat game in the vein of Star Fox or Panzer Dragoon. And you even get a Portal gun at one point.
Now that I've gotten the negativity out of the way, let me state that Darksiders does all of this really well. Sure it's not original, and sure it doesn't really top any of the games that inspired it, but all of the elements in this everything-plus-the-kitchen-sink style game work well and work together. And the game introduces new items at a regular pace, helping to keep things interesting for a while.
For the most part, however, this is a Zelda game with God of War's combat. You enter one of the game's dungeons, navigate around an initially limited path and solve puzzles to find a new item (usually an equivalent to a Zelda item like the boomerang or hookshot). You use that item to trek further in the dungeon, solving more puzzles, until you reach and defeat the boss. It's an effective formula that's enhanced by the smooth flow of its combat. The combat plays just like a poor man's God of War, with two attack buttons (plus whatever item you have equipped) and a focus on linking together combos based on direction. Thanks to satisfyingly smooth animation and kills, and the ability to upgrade combos, the combat never gets stale, although it does feel a tad bit too simple.
Where Darksiders fails to keep up with its inspirations is in the story department. The basic premise is that you, War, one of the four horsemen, have been prematurely called for an untimely end of the world. The Council seeks to punish you for your actions and sends you to stop the one who caused the whole fiasco. As you go on, you find that things aren't what they seem (big shocker) and plan to take down the big villain once and for all.
It's a relatively simple, though not always clear, plot that's hampered by some terrible execution. Lines are frequently forced and delivered melodramatically, plot twists are either unsurprising or lacking any real punch, and the worst part is the characters. War is angry like Kratos, but has none of the back story pathos to make you sympathize. The characters that War meets rarely have the kind courtesy or charming quirks you might find in a Zelda game. And basically nobody is likeable, making it hard to care about anything that happens in the plot.
This isn't to say that the presentation is universally bad: just the story. The graphics are actually quite good. Although not the most detailed graphics around, they add a bit more color to the standard post-apocalyptic setting, lending it a kind of comic book flair that makes the lower detail environments easy to overlook. Characters are for the most part smoothly animated, and enemies are standard demonic fare, although the details add a nice, gruesome, intimidating effect. Notably, however, the PC version lacks most graphics settings that are expected standard in the industry, leaving only resolution and VSync options. Sound effects are standard, with a booming soundtrack that sounds like it came from virtually every action movie ever, and the voice acting is fairly standard, working best with some of the truly evil voices used by demons, but let down by the ridiculous delivery of some lines.
Darksiders isn't really required playing. Nothing here hasn't been done before, or done better. However, for what it's worth, Darksiders is a very successful clone and a fun 12+ hours for those who were already interested.