Phantom Vigor is a 10th level cleric Utility power that was introduced in Heroes of Shadow.
Phantom Vigor
Cleric Utility 10
Tendrils of shadow unfurl around you to wrap your allies, drawing off their health to grant superior strength and speed.
Close burst 5
Target: You and each ally in the burst
Effect: Each target loses a healing surge and gains temporary hit points equal to his or her healing surge value. In addition, until the end of the encounter, each target gains a +2 power bonus to speed and a +5 power bonus to Athletics checks and Acrobatics checks.