SiN is a
first-person shooter video game based on a modified version of the
Quake II engine developed by
Ritual Entertainment and published by
Activision in late 1998. The game was later released over
Steam platform on April 5, 2006, either as a standalone product, or bundled together with its sequel,
SiN Episodes. It was also released, along with its expansion pack on
GOG.com on January 30, 2014, DRM-free and fixed for modern hardware.