This a cheesy little tool that emulates MZX's editor...in MZX. It lets you place simple enemies and construct little levels and stuff, with customizeable win conditions, but honestly, MZX itself is far better suited than this. I guess the author only wanted to say "Hey, it's possible!"

This is probably the most useless world ever made for MZX. Basically, it's a editor for the game made with the editor. At least this guy proved it's possible to do it...