Anomaly is a standalone S.T.A.L.K.E.R. mod powered by an x64 version of the X-Ray engine. Starting with version 1.5.0 Anomaly uses a custom engine build called the XRay-Monolith engine. After almost one year of development of the Anomaly 1.5.0 update, the mod continues its way on expanding and adding new features while maintaining a high level of quality and replay value.