The Mephitis was an EF76 Nebulon-B escort frigate in the Imperial Navy during the Galactic Civil War. It was stationed near Polic Massa where it served as home to the 481st Experimental Starfighter Testing Squadron during testing of the TIE/ph phantom, an Imperial starfighter fitted with an experimental cloaking device. For its defense while the TIE phantoms were out on operations, the Mephitis carried a mixed squadron of TIE Defenders from the 29th Fast Attack Squadron and TIE/IN interceptors from the 92nd Interceptor Squadron.