High Quality Content by WIKIPEDIA articles! Spring (formerly known as TA Spring or Total Annihilation: Spring), is a free open source RTS game engine created by the Swedish Yankspankers. Originally intended to bring the gameplay experience of Total Annihilation into three dimensions, the engine has since evolved to support a plethora of more modern and more flexible features, including built-in high-level extensibility through a Lua scripting interface. The core game engine is licensed under the GNU GPL.