Alpha Legion Tracking Implant
This implant is a tiny, near-undetectable device planted at the base of the skull.
This implant gives off a signal when it is in proximity with another alpha legion implant. This signal transmits as a small sound in the heretics ear. The implants are programmed to stop transmitting after 10 seconds of proximity to avoid detection and annoyance at the sound it makes.
All of the heretics are implanted with one of these.
Effective reception range of the tracking implant is 30-40 feet.