Ive had PTSD educed hallucinations (those arent fun), hallucinations from sleep deprivation (nor are those), and hallucinations from salvia (those are fun). Im not sure if salvia is legal in the the UK, but if it is, you might want to give that a go. The tea is actually pretty tasty to!
Anyways, it all depends on what it is. The ones that were salvia induced were amazing. I saw all sorts of crazy things, and it was very trippy.
Now, PTSD hallucinations are NOT fun in the least. Flashing back, and re-living your worse memories is one of the most horrible things that can ever happen IMO.
Sleep deprivation...Not necessarily hallucinations, but similar experiences. I guess its not as severe or great of hallucinations.
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Who do you carry that torch for, my young man?
Do you believe in anything?
Do you carry it around just to burn things down?