Written by Clive Townsend and published by Durell Software in 1985, Saboteur is a stealth action platform game that was something of a hit with ZX Spectrum users back in the day.
You play a ninja on an infiltration mission, who arrives by boat and who must sneak around a large warehouse, looking for a floppy disk with “names of rebel leaders” on it, and then make good his escape. Unfortunately the warehouse is crawling with guards, dogs, and automated security systems, all of which must either be destroyed or avoided. The level of difficulty can be chosen by the player beforehand, and there are nine difficulty levels to choose from (one to nine), and the higher the level is: the more concentrated the defence.
The saboteur can run, crouch, climb ladders, do a high kick, and throw shuriken, and – for the time – was a versatile and rewarding character to control. Playing Saboteur now still brings some joy, and the game has aged reasonably well, considering the Spectrum‘s limitations.
A much bigger (and better) sequel (by the same author and publisher) came out the following year, in 1987.
More: Saboteur on Wikipedia