SCP-999 appears to be a large, amorphous, gelatinous mass of translucent orange slime, weighing about 54 kg (120 lbs) with a consistency similar to that of peanut butter. Subject’s size and shape is easily malleable and can change shape at will, though when at rest, SCP-999 becomes a rounded, oblate dome roughly 2 meters wide and 1 meter in height.