Mac OS X Softwares to Modding Support

Simutrans is a cross-platform transport simulation game where you build and manage a global transportation network for passengers, mail, and goods across land, air, and water.

Alien Swarm is a free-to-play, top-down cooperative shooter developed by Valve. Players control a squad of marines battling hordes of extraterrestrial enemies in various sci-fi environments, emphasizing teamwork and tactical gameplay.

Quake is a landmark series of fast-paced, first-person shooter video games known for its pioneering 3D graphics, intense multiplayer deathmatch, and distinctive dark sci-fi/fantasy blend. It emphasizes speed, skill, and movement.