Mushrooms, Ayahuasca and whatever can be useless but if you are not prepared for what you will see / hear you can go crazy. I've heard some scary stories. Also experienced a bit myself around other people taking LSD and shit, some people think they can fly and jump out the window - personally my story was that a guy I took LSD with forced me into a Samurai sword battle and shit.
If you're going to take hallucinogens take it alone - even some people you think are sane might go crazy on you. My buddy said he took mushrooms with a guy and the buddy tried to kill him with a knife. Imagine being high on mushrooms and your friend is trying to kill you.
I recommend start with 3grams of Magic Mushrooms during DAYTIME. Last about 6-10 hours so take it 8-12am, if you take it at nighttime it feels scary. Listen to some music, you can see / feel the vibrations bouncing off the walls.
I can't even describe what the 10 grams Mushroom Trip is like though, I literally died. But once I died I came Alive, can't describe it with words yet.