Operation: Shadow Debt was an event released with Hotfix 18.4.1 on PC, and Update 18.5.6 on consoles. Calling in his favor from The Second Dream, Alad V requested the Tenno's aid in hunting down the Stalker's newly minted Acolytes. For PC, this event lasted between January 26 to February 3, 2016. For consoles, this event lasted between April 14 to April 22, 2016.