Monster Manual Comparison! (MD 225)

3034.894 - 3056.615 Teos Abadie

And the idea is that different parts would glow in the dark. We know that the gelatinous cube, myconid, gasp, or beholder in green slime all appear to have the treatment. There are probably others as well. Those are just the ones either named or shown in pictures. Personally, whenever I try to dim the lights, Nobody can see what the heck they're doing, and it just is disappointing.