User blog comment:Chase999/Liliana, the Demon-Singer/@comment-10256611-20140110124818/@comment-22636720-20140110143131

basically its a timer skill once activated she starts singing and the damage is given to enemies directly infront of her in a 20 degree cone and you gain stacks, the closer you are to her the more that stacks the enmies get. the enemies also get stunned if the stacks reach 20 and cannot get stunned after the stun they just got.