Flame Geysers are found in The Catacombs in Pre-Searing Ascalon and are involved in The Necromancer's Novice quest. They are indicated by large round glowing green circles on the floor. Stepping on these traps causes them to trigger and do a large amount of damage. There are three of these traps, all located in one hall in The Catacombs, and each can be triggered safely by using Animate Bone Horror to summon Bone Horrors from nearby corpses.