You invoke ancestral spirits of battle. Under their shadow, your allies fight with greater might.

Daily   ✦     Primal, Zone
Minor Action      Area burst 5 within 10 squares

Effect: The burst creates a zone filled with ancestral spirits that lasts until the end of the encounter. While within the zone, your allies gain a +1 bonus to attack rolls.

Published in Player's Handbook 2, page(s) 123.