Clawfoot Berserker Rage is a daily power available to the Barbarian class at level 5.[PHH2:PH2]
Clawfoot Berserker Rage
Barbarian Attack 5
You channel the behemoth's fury to avenge injury to allies who fight alongside you.
Melee weapon
Target: One creature
Attack: Strength vs. AC
Hit: 3[W] + Strength modifier damage.
Miss: Half damage.
Effect: You enter the rage of the clawfoot berserker. Until the rage ends, when any ally within 5 squares of you becomes bloodied, you gain a +2 power bonus to attack rolls until the end of your next turn and can make a melee basic attack as an immediate reaction.