El Jazzar's Treasure
Green Slime (species)
Medium Ooze (Hazard)
Detect: It takes a DC 10 Wisdom check to notice the green slime under normal conditions and a DC 12 Intelligence check to identify the hazard for what it is.
Effect on Creatures: The slime can detect the air vibrations and temperature of living creatures. When it does, a sheet of it large enough to envelop the passing creature drops from its resting place onto the target. The target must make a DC 12 Dexterity saving throw to avoid the sheet, making the saving throw with disadvantage if the slime was unnoticed or not considered to be a hazard. On a failed save, the target takes 1d6 acid damage, and takes another 1d6 acid damage at the end of each of its turns during which it is still in contact with the slime.
A creature that steps in a patch of green slime on the floor receives no saving throw to avoid taking damage.
Effect on Objects: Against wood or metal, green slime deals 2d6 acid damage per round, dissolving about an inch thickness of material each round. Green slime does no harm to stone or glass.
Countermeasures: Green slime can be scraped off or killed by taking 11 damage or more from weapons, cold, or fire. Dealing damage to the slime also deals half damage to the creature it is covering.
Green slime is a dangerous, unintelligent variety of normal algae that forms in moist subterranean environments. Bright green, wet, and sticky, it clings to walls, floors, and ceilings in patches. This plant is a slow- growing hazard that feeds on flesh, plant matter, and metal.