Vital Strike(Complete Mage)
Level: Assassin 3,
Casting Time: 1 swift action
Duration: One attack
You suddenly see two versions of your target, one a split second ahead of the other, allowing you to target the holes in his defenses.
You gain temporary, intuitive insight into the actions of your foes.
Your next single attack roll (if it is made before the end of the next round) is considered a sneak attack, even if your foe is neither flat-footed nor flanked.
This spell does not allow you to sneak attack creatures normally immune to such attacks, nor does it allow you to make use of other abilities—such as certain feats—that deal ability damage, or otherwise grant you extra benefits, when you make a sneak attack.