My worst trip (which I still don't regret) was when I took a strip of acid, and then a friend who was 4 tabs in pulled out some tannerite that he hadn't mentioned beforehand and started shooting at exploding targets. I was totally lost in the swirl of drugs, vaguely aware of the explosions and worrying about the safety of my friends. I think I could've handled it a lot better if I had known about the exploding targets before the entheogens kicked in, but still, the 4th of July probably isn't the best time for those particular drugs :/