B+ Magic Mushrooms For Sale. The b+ mushrooms is a domesticated hybrid mushroom of unknown origin. Under a microscope, this strain closely resembles a P.cubensis but shares some characteristics resembling a P.azurescens. It’s a unique P.cubensis strain and performs very well indoors making it a popular strain for home hobbyists. It tends to yield larger than average fruitbodies that range from moderate to potent for a P.cubensis strain. buy b+ magic mushrooms online.