the most intense thing to do would be the Holy Grail. It is a mixture of several plants ........ Amanita Muscara, Psilocybin, papaver somniferum, and syrian rue
Its the true gateway to the heavens
do a search for James Arthur and Amanita
other than that lsd is the highest by wieght followed by Salvinorin
other than that Datura, Angels trumpet, jimson weed and belladonna