Someone has created a spell called 'Frozen Fire'. It is destructive enough to destroy entire armies and castles. The creator of the spell has raised an army that includes medusas, ettins, orcs and harpies. To make matters worse, an invisible assassin is hunting down the surviving Mystasian noble lords. To survive the spell, they must learn who has created it. The citizens of Mystasia have no choice but to turn to the dark races for help; but the dark races are reluctant to help the country that betrayed them centuries ago.