Cunning cyclone
rogue attack 13
Requirement: wielding a light blade
Target: each enemy in burst you can see
Attack: Dexterity vs. AC
Hit: "1[W] + Dexterity modifier damage."
special: If you have combat advantage against more than one target, you can deal one die of Sneak Attack damage to each target that you have combat advantage against, rather than dealing all your Sneak Attack damage to one target. This counts as one use of Sneak Attack, regardless of the number of targets.[MP:80]
Cunning cyclone is an encounter power available to rogues at 13th level.