is tripping on mushrooms a pre-requisite

No, not really. But the show will certainly appear different. I thin without shrooms you catch the subtle references and the gags, but with shrooms you'll just have an awesome time. Your choice

No, but egg in soup is.

If you keep an open mind, you`ll discover dark secrets.

I think you just have to have a sense of humor. I don't do drugs and found it absolutely hilarious!