Perplexity

Perplexity, created by Ian Collinson for the Acorn Electron and BBC Micro and published by Superior Software in 1990, is an isometric pseudo 3D maze game which graphically resembles the 1987 arcade game Pac-Mania (both the maze view and main characters) but while it does share some gameplay elements, the game is a much more calm and organised playing experience with the emphasis on puzzle-solving and as such has been described as a 3D version of Repton.