Unreal Engine
Unreal Engine is a professional suite of tools and technologies used for building high-quality games across a range of platforms.
The Source SDK is a software development kit compiled by Valve Software that is used to create maps or mods for the Source engine, with the exception of Left 4 Dead, Left 4 Dead 2, and Alien Swarm.
The Source SDK is a software development kit compiled by Valve Software that is used to create maps or mods for the Source engine, with the exception of Left 4 Dead, Left 4 Dead 2, and Alien Swarm. These games are packaged with their own SDKs, called the Left 4 Dead Authoring Tools, the Left 4 Dead 2 Authoring Tools, and the Alien Swarm SDK respectively. They are all extremely similar to the Source SDK, but tailored slightly to suit each game's needs.
Productivity Developer Tools Games File Sharing Travel and Location
games maps sdk mapping game-development mod dev-kit steam valve left4dead level modding
Unreal Engine is a professional suite of tools and technologies used for building high-quality games across a range of platforms.
Free Mac OS X Windows Linux
Superpowers is an HTML5 development environment for making 2D and 3D games. It can be extended with plugins and lets you collaborate in real-time.
Free Open Source Mac OS X Windows Linux
Xenko is an open-source C# game engine designed for the future of gaming. It comes with a full toolchain and is especially well suited to create realistic games but allows you much more!.
Freemium Windows
Amazon Lumberyard is a free AAA game engine deeply integrated with AWS and Twitch – with full source.
Free Windows
Maratis is a portable, simple and visual game development tool designed for artists and developers. The Engine has been tested on Windows, Mac, Linux and iOS and can be used virtually on any platform. Maratis is Free and Open-source.
Free Open Source Mac OS X Windows Linux iPhone iPad
Fabric Engine is a platform for developing high-performance custom tools for visual effects, games, real-time visualization and VR/AR work.
Free Open Source Mac OS X Windows Linux
A game and graphics engine for multiplayer, cross-platform, real-time 3D action, GPL licensed.
Free Windows Linux Lua