Molten Sal (named simply Molten Salamander in Co-op Missions) appears in the level The Vermillion Problem. Part way through the mission, Molten Sal will spawn on the lower right corner of the map, but only appear for as long as the surges flood the low ground. The salamander has low health, attacks units in a line for moderate damage. The challenge in defeating Molten Sal comes from the short time of the lava surges, and unless a large force is committed to killing it the creature may burrow before it can be finished off. It may take multiple surges to actually defeat the worm, but after the map is cleared and defenses are established it can be whittled down relatively easily.