Aquaventura
Trivia
Demo version
This game had been under development for almost half a decade. Copies of a demo version of Aquaventura with the first two levels were available sometime in 1989. Though it had a lot of bugs, it featured the usual high quality graphics from Psygnosis with an animated end sequence as well as some music from David Whittaker. That version of Aquaventura was one of the first games to use the "vector ball" technique even before it was ever used in any kind of Amiga "scene" demo. Unfortunately the game released in 1992 looked (and sounded) completely different than the appealing demo version released years before...
The demo also had an unused drawn intro, that was later replaced by a rendered one. It can be watched here: http://amiga.lychesis.net/game/Aquaventura/Aquaventura_AltIntro.html
There is also an unused game-over animations and work-in-progress graphics http://amiga.lychesis.net/game/Aquaventura.html
Trivia contributed by chromax, Karl Clemens.