We are willing to go over the shadow warrior for you. Let us start out with its basics.
   Along your career as a Shadow Warrior, you'll acquire three stances, of which only one can be active at a time. Each has a 5 second cool down when switching. To clarify, you can't enter once stance, make an attack, and immediately switch stances again. It should be noted that switching stances does not throw a global cool-down at you for all of your skills. Certain skills require you to be in a certain stance. That being said, you must take a first look at these stances.
   Scout Stance increases your Ballistic skill by X and also gives your bow attacks a 10% range boost. If you're standing away from the crowd and just want to pluck away at range, this one's your choice.
Assault Stance is probably the best stance in terms of overall bonuses and you will get X to weapon skill and strength, with a 100% boost to your armor. While the armor bonus is very nice, it doesn't make up for the fact that unlike tanks you don't get a shield or very high avoidance bonuses. That roughly translates into you constantly getting hit, but for less damage. Don't get me wrong, it raises your survivability considerably, but it isn't by any means a calling card to fill in when your big guy calls out sick. The strength and weapon skill bonuses are very nice, and you'll definitely see them making a difference in your melee damage.
Skirmish Stance increases your Toughness by X, and increases the chance for your bow attacks to critically hit by 5%. The toughness stat is about as irrelevant as it gets; if you're getting hit hard, you're going to die–switch to assault stance to mitigate the damage as best you can and either gain some distance, or try to take them down. You could always try to out DPS them in skirmish or Scout stance as well. After all, they usually can't kill you if they die first.
To be honest, it is hard to really describe a play style that a Shadow Warrior should stick to for success. Eventually, somewhere near level 20 when you have enough abilities to really get a feel for your career and what to expect down the line, you'll find a few key skills that you can center yourself around, and add in a few utility abilities here and there. Early on we found out that the situation dictates your tactics, in other words, the terrain you have to work with and what kind of enemies you're facing.
As a matter of fact, Eagle Eye is the ability that many Shadow Warriors will use most when you start the game with this ability. Therefore it is your basic ranged attack with high damage and a moderately long build-up. This does a considerable amount of damage, and if you can keep an enemy in sight and range long enough, you'll really leave them in a world of hurt. You can use eagle eye in any stance.
The Shadow Warrior receives Area of Effect root ability like so many other careers. You have the ability to root all enemies every 20 seconds in place within 30 yards. Damage will break the root 50% of the time. It's really a key ability to any class that can access it and master its use. You can run into a skirmish and root down an entire group, or save a healer who is attempting to flee by rooting his target in place. The uses go far beyond escape and setting up distance, you can take an entire mass of enemies out of a scenario for a few seconds by throwing this ability down just before you die, leaving them stuck in place a few moments while the rest of your team continues to work toward accomplishing its goals.