It is a development of Spaceman's previous Ant Attack, and uses an updated "Softsolid 3D" isometric graphics engine.

They must lure the zombies into following the player and then trick them into falling off the edge of tall structures more than three blocks high.

[5] The city is made of blocks which can be rearranged by the player to make the zombie cull easier.

Your Spectrum revealed in another tips article that there was a second hidden city accessed by entering a codephrase.

Although a wiring diagram was supplied with the game,[5] the interfacing code had been tested on a Yamaha DX7 with a ROM containing bugs and the circuit would only work on that particular synthesizer.