Green’s Dictionary of Slang

1. (orig. US) a person or event that is totally confusing or amazing.

1966-68		F.S. Perls Gestalt Therapy Verbatim (1969) 210: I don’t want to be a mind-fucker. I don’t want to be so pompous, I don’t want to be so much better than everybody else. I just want to feel like I’m part of people.
1969		Woodstock [film] This thing is a real mindfucker!
1971		E.E. Landy Underground Dict. (1972) 133: Mind fucker...person who attempts to manipulate another’s thinking without consideration for the other.
1980		A. Maupin More Tales of the City (1984) 130: Jon shook his head incredulously. ‘That is . . . a mind-fucker.’.
1996		New Yorker 26 Feb. 84: Sigmund Freud, figurehead for all professional mindfuckers [HDAS].
2005		E. Garnet Impulse Archaeology 1: [A] reputation as a shapeshifter, a seducer, and a mindfucker.

2. attrib. use of sense 1.

1999

G. Held et al. Generation Ecstasy 303: DBN is a record label specializing in PCP-style industrial-strength hardcore and mindfucker acid [rock].