Freshbox Magic Truffles, also referred to as sclerotia, are truffles that are related to magic mushrooms. Until 2008, you could actually buy magic mushrooms legally in the Netherlands, but the laws have been changed. While you cannot buy magic mushrooms anymore, you can still buy magic mushroom grow kits and magic truffles, completely legal*.
Both contain the active substances psilocybin and psilocin, which are mainly responsible for the psychedelic effects, and some other alkaloids. Psilocybin and psilocin, which act as strong serotonin agonists in the brain, are scientifically proven to produce hallucinogenic effects that may include spiritual experiences, alterations in mood, and distortions of perception. The other tryptamine alkaloids present in Freshbox magic truffles are not so well researched, but it is known that their concentrations vary between the truffle strains, which explains the different effects they provide.