Nicotine. Makes you feel like shit and wonder why you smoke cigarettes. But as for real psychadelics, I've only tried shrooms and lsd, and lsd...
Weed is in a class of its own. And psychadelics are far and away the best. Non-addictive mind-expanding fun.
Like others have said, just eat shrooms and smoke beforehand or during your trip. It is a delicious combination.
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