In Reality Check you are actually playing as a player who got pulled into the world of Half Life 2 and now has to find his way through Improbability Zones, Combine Assaults, and even defeat the person that caused the improbability zones in the first place.
Faine, from Fur Affinity, has given his permission to use this music in the mod, Reality Check. To hear more of his music visit Furaffinity.net
One of the planned bosses for the mod has been inspired by this song. The combine calling for it(that is how my mind saw it when i first herd this song)