...The release includes all major game subsystems: rendering, physics, network code, game logic, and tools (map compilation, asset packing, etc.), enabling full builds on Windows, Linux, macOS — assuming you provide the original game assets. Because the source is available, there are many community forks and improved engine builds (and ports) that modernize graphics, compatibility, input, mod support, and add enhancements while preserving core gameplay. The GPL-based release also enables modders and developers to study and extend the engine for learning, custom mods, or even entirely new games.