3D Rad is a free game creation software. The program is quite simple, but allows you to create relatively complex games. There are many examples that come with 3D Rad.
3D Rad allows you to work with light, sounds, particles, textures, shaders, animations and many other elements of game construction. Transparency can be used to create textures. Objects in the game can be equipped with artificial intelligence (two examples of AI are in the project database).
The level may be raining or snowing, for example. To do this, you need to apply effects. In addition to weather conditions, you can decorate your game with light spots, blurring, glare, water, etc. Objects such as fog, fire, mirror, etc. are also supported.