At one point I could have included Dave Allsops SLA Industries. On it's face SLA was a fantastic Far Future sci fi game. Complex, Dangerous and filled with Strange personalities and even stranger monsters. At the time there was also something called the Writers Bible (The Truth) that loosely describe the reality of the backstory. The Truth as it was called firmly placed the blame for all the Pain and Terror of this world on the shoulders of a child whose "imaginary" reality became his real reality. This backstory was rendered null in later editions. If one were to include this "truth" and Integration 20 I'd say this is the winner, but alas...
Nephilim was a quirky game about incarnated elemental spirits taking human form and their battle with notable Secret Societies.
I'd be remiss if I didn't include Kult, but I won't go into details because I've written about it already.
(This is an actual photo of my second copy of this game I picked up at half price books, this year. Dat Price Sticker)
Numenera isn't nearly as weird as Monte would like to think it is. It tries too hard.
All those game aside, the winner for me is:
Mechanical Dream was like a Mushroom induced bizzaro tripfest.
Characters reside in the world of the dual world of Kaïnas and Naakinis, a 30,000 mile disk lit by a sun-like orb called the Pendulum. This disk is surrounded by the Sofe, a 40-mile-tall wall of black ether that kills that few, if any, have ever returned from. Kaïnas (the rational world) and Naakinis (the mythic world) exist with overlapping topography and ecosystems. Flora and fauna of Kainas are scaled normally by real-world standards, while Naakinis exists on a much larger scale (such as the "Kioux" trees that reach many miles in height). In general, the word "Kaïnas" denotes the disk illuminated by the Pendulum, but "Naakinis" extends further and includes whatever lies in and beyond the Sofe.
What The Fuck?
So the entire population of this world was also addicted to a fruit named Orpee that was basically pure Life Force. Characters could use this to fuel all kinds of strange abilities.
This game is only playable on massive amounts of drugs.