Evasion

Evasion is one of the Rogue's defensive abilities, boosting their dodge rate by 50% and reducing the chance that physical ranged attacks hit them by 25%. It is an absolute increase, so a base dodge skill of 10% would rise to 60% when Evasion is active. Evasion can be learned at level 9 for.

Improvements

 * Glyph of Evasion increases its duration by 5 seconds.
 * The 3 piece bonus of the Deathdealer's Embrace armor set reduces its cooldown by 60 seconds.

Tips and tactics
Warriors have abilities which feed off of their opponents dodging, so be careful of using evasion against them. Consider using evasion early on in fights with warriors, as the damage taken from Overpower will be negligible in comparison to the full amount of melee damage a warrior can deal. Note that depending on your dodge rate and your oponent's attack speed you may happen to dodge whenever overpower cooldown is up anyway, allowing them to use it often, with or without evasion.

Won't let you dodge attacks made from behind, and does not work at all when you're stunned. Choose the right moment to use it, as most melee classes can counter it with non-melee-based attacks: paladins can stun you with Hammer of Justice, druids can root you with Entangling Roots, rogues can use Blind, etc. At high levels you can benefit from either Cloak of Shadows or even rank 2 of Evasion, but keep this in mind anyway.

In any melee situation, it will significantly lessen the damage you're taking. If your total dodge + parry is bigger than 50%, it may even make you untouchable - enemies won't be able to hit you at all. This can often buy enough time to finish off a mob, or to survive an add, or wait for the tank to peel a mob off you.

Its main weakness is the relatively long cooldown time (this can be reduced with Glyph of Evasion). Save it for when you need it, but don't be afraid to use it when things are looking iffy.

Using evasion during certain raid encounters (such as Instructor Razuvious) can be key to your raid's success.

If your tank dies when the boss is almost dead, Evasion may be a lifesaver. Pop Evasion as soon as you see that the boss targeted you. You can now tank the boss for 15 seconds, which might just give enough time to kill the boss. Vanish just before Evasion ends. If there is more than one Rogue in the group / raid, you may chain Evasion-tank the boss, giving even more time to DPS.