Right as combat begins, you disappear into the shadows.

Daily   ✦     Shadow
Free Action      Personal

Trigger: You roll initiative

Effect: You gain a +4 power bonus to your next damage roll. In addition, you become invisible and silent until you hit an enemy or until the end of the encounter. After hitting the enemy, you remain invisible and silent until the end of your next turn.

Published in Dragon Magazine 379, page(s) 24.