Magic truffles are the sclerotia of Psilocybin mushrooms that are not technically the same as "mushrooms". They are masses of mycelium that contain the hallucinogenic chemicals psilocybin and psilocin.
In October 2007, the prohibition of hallucinogenic or "magic mushrooms" was announced by the Dutch authorities. The ban on mushrooms did not outlaw the hallucinogenic species in sclerotium form, due to authorities believing it to be weaker than the mushrooms. Psilocybin truffles which once made little sales became the only legal option to produce. Today, smart shops in the Netherlands offer magic truffles as a legal alternative to the outlawed mushrooms.