Red Lums can become Black Lums when they are frightened, and making them laugh will change them back. Perhaps, these Lums are special in some way. These lums seem to react with emotions, this is not explained however. Red lums could, in fact, be organic. They have appeared in all platforming Rayman games, with the exception of Rayman 1, where they are round balls (it could be, however, assumed that these round balls still are Red Lums as both fulfill the same purpose of healing Rayman).