These vessels were used by the Xindi Reptilians in the mid 22nd century. Like the Insectoids, the Reptilians were considered to be one of the most warlike Xindi factions. Their ships are primarily designed for combat operations, and carry a heavy armament. They are also heavily armoured, but they do have a weakness in the power system which the Xindi Primate Degra helped to design, and hits in the correct place can incapacitate one of these vessels relatively easily.

The ships were first encountered when they attacked the NX-01 to recover Rajiin, a Xindi agent who had been aboard on a covert mission to gather biometric data on the crew. Ships of this type visited the kemocite production facility whilst the NX-01 was there7, and were at the weapon proving ground which Captain Archer discovered. The NX-01 battled several Xindi ships, including Reptilian Warships, when it penetrated the Azati system in an attempt to destroy the final version of the Xindi Weapon4, and ships of this type battled Archer's ship during the theft of the Xindi weapon and it's subsequent journey to Earth. During this period the MACOs carried by the NX-01 raided a Reptilian warship to recover Ensign Sato from captivity. At Earth Commander Dolim's warship was successfully engaged by Shran's warship the Kumari.