Repton 3 was the third in a series of Boulderdash like games released by Superior Software. The games were originally made for the BBC Micro computer.
The original game was written by Tim Tyler.
Repton was also made for the Spectrum and C64. Repton 2 was also made for the Spectrum.
Repton 3 was advertised for the Amstrad CPC and was planned to be released in the spring of 1988 but at this time it remains Vaporware.
In 2008, Arnoldemu started work on a conversion of Repton 3 to the Amstrad CPC. The official version did not surface, and being a fan of the Repton games (having owned them on the BBC Micro) he decided to make a conversion.
The conversion was progressing well, and then he contacted Superior Software in order get their permission that he could distribute this version for free. Permission was denied and development was stopped. This version will not be released. So even the conversion stays Vaporware.
NOTE from Arnoldemu: I had implemented most of the UI (title screen, map screen, information screen, load level screen, and password screen). I had implemented most of the game logic (collection of gems, crown, teleporters, eggs cracking, lizard enemies, fuzzball enemies). There are bugs because it was never completed. The game matches the BBC screen size and uses Amstrad's hardware scrolling and double buffering. My version could load the BBC data files directly if they were converted to binary files on the CPC. The graphics from the level files are converted into a form the CPC can display, so in theory any level designed for the BBC will work with this version. I respect the views of Superior Software, this is why it remains unfinished and unreleased.
Tim's website: http://timtyler.org/
Repton at wikipedia: 
Repton flyer at 8bs.com: