A 4E adventure for levels 7-9. In a world of arcane magic and divine might, some secrets are best left hidden. When the forces of the wicked Mountain King discover an eldritch weapon of unmatched power, the future of the Northlands hangs in the balance. Following in the wake of bloody, madness-induced slaughter, can the heroes prevail where an army has perished? Blood and madness are in store, for where Lord Ablair the Corruptor passes, death must surely follow. Only the most cunning and courageous of heroes can triumph against the Citadel of the Corruptor!