The influence that Anomalies have on real, ordinary things. Minor Encroachment rarely manifests visibly. Major Encroachment manifests in various ways depending on the corresponding Anomaly. Encroachment caused by the same type of Anomaly can also differ from environment to environment.

According to the Countertransference Theory, the closer humans get to Anomalies, the more they learn about and research them, the more susceptible they become to both physical and mental influences.