Your sudden move causes the enemy to flinch, setting up your ally's next attack.

Encounter
Minor Action      Melee 1

Target: One creature

Effect: You make a Bluff check opposed by the target's passive Insight check. If the check succeeds, one ally adjacent to you gains combat advantage against the target for that ally's next attack against it before the end of your next turn.

Published in Player's Handbook 3, page(s) 166.