SiN

SiN is a first-person shooter released in 1998 and was developed by Ritual Entertainment using a modified version of the Quake II engine. It is a science-fiction first-person shooter, where John Blade discovers a mutagen being developed by SinTek corporation.

The game was initially plagued with bugs on early release, which were eventually patched in the later versions. Currently, there are two major versions - 1.12 as found on Steam which has compatibility issues with the expansion pack and with changes due to copyright and controversy considerations, and 1.11 as found on GoG.