Could use work...
The most powerful thing in this game is the world. All the cities and areas feel alive and real. People are talking, moving, minding their own business. The birds, the environment, they're all full of detail and you can tell a lot of work was put into this. It makes the adventure so charming just to play through. It's so good, you might just want to spend the game exploring.
The game's next best thing is how you move. You can climb, crawl, jump, run, from building to building, all so fluidly. It's spectacular. It all comes together well and it's a blast to just explore the towns you'll be in.
The rest of the game... Kind of shallow and a let down. For most of the game, you'll be repeating the same missions over and over again. They're not terrribly difficult either. Side missions give you more health, but the combat is shallow too.
Combat allows you to use four weapons: You fists, sword, dagger, and hidden blade. The hidden blade is the Assassin's trademark weapon, and for a reason. Although you have options, the most effective way to fight (once you learn it) is the counter attack. Counter with the hidden blade ALL THROUGH the game, and fighting becomes a breeze, even against over a 100 foes.
The stealth parts of the game makes you question the AI's intelligence too. Although it's a great, alive world, it must be full of idiots. Mentally retarded (I'm being literal here) walk around, randomly hitting you. I'm pretty sure their first instinct isn't to ALWAYs hit you, but it is in this game. Also, if you're being chased by people with lethal weapons that can easily kill you, here's your options:
Sit on a bench
Pray
Pray with people
Climb buildings, hide in hay, and hope they don't see you
Real stealthy eh? No, just stick with Metal Gear. How do they not notice the only guy with a hood and weapons all over him?
Of course, with crappy stealth and combat, and repetitive missions, the game goes down hill. The fact that you lose ALL your skills and weapons early in the game when you had them before doesn't help either.
So, this game had TONS of potential, but its flaws make it seem like a prototype for an upcoming game that should have more features. The story is interesting enough, and exploring cities is always a joy. But the rest of the game is so shallow, you won't really care about finishing the game. And when you do, you're left with a confusing ending.
It's good and a lot of work has been put into it resulting in a game that can be improved upon, but it's fun on its own. I suggest a rent.
On the plus side, the game's sequel looks like it's fixing all the problems this one has. So if you even liked this game a little bit, be sure to check out the sequel for sure, as it will definately be more interactive, interesting, and varied.