3D Construction Kit, also known as 3D Virtual Studio, is a utility for creating 3D worlds in Freescape.

This package allows users to create their own 3D worlds, using technology related to the Freescape universe seen in games such as Castle Master and Driller / Space Station Oblivion. Pull-down menus allow objects to be created and positioned, with movement loops and simple animation defined. A network of rooms can be created.

A simple BASIC-style language is integrated to allow puzzles and conditions (open a door when a key in placed into it, for example). You can also include enemies which must be shot. At any moment you can enter the gameworld to test it.