Jet Medallion

Black spells you cast cost {1} less to cast.
Discovered by workers building a new generator just outside the city limits, the only place there was still space for one. The item was given to researchers within the main city for inspection. Evidence acquired form an ancient language on its metal frame praise the man who used to own it, a tyrant that could use the medallion to turn death and suffering into a power that fueled his great constructs.