Rulings and Errata
You can combine multiple Creeping Death spells to reduce all Monsters’ Health totals by more than 2. If a Monster’s health is reduced below 1, it goes to your discard pile. You do not gain any XP for Monsters removed by the Creeping Death. You can potentially kill several monsters at once with Creeping Death. New monsters entering the Dungeon Hall are unaffected by this spell.