Mac OS version 7.5 or higher. Quake for the Macintosh. QuickDraw 3D 1.5.4. There are two main objects in Quake, brushes and entities.
Brushes are what makes up the levels themselves and include walls, water, doors, bridges, etc.
Entities are the things that you interact with, such as enemies, weapons and ammunition, switches, etc. Fortunately, Quiver has an interface that makes adding these important two elements easy. All you have to do to create any object is to select the object's icon, and click and drag in a view. Once you have the object made, you can flip, hollow, resize and rotate it until it's just the shape, size and position that you want. An advanced option is carving, where you can create a new shape by cutting one brush out of another.