An Orion vessel was a class of spacecraft used by Orion Syndicate. It was first encountered by the Federation in 2270, identified by its Orion markings.
This type of Orion vessel, which was not identified as a starship, was armed with standard phasers, described as weak with a diffused, low-quality beam, and such a vessel could neither outrun nor outgun a Constitution-class starship, but was powerful enough to overtake a Huron-type freighter. This type of vessel also emitted a unique trail of radioactive waste that was visible on a spectral analysis.
Orion vessel in 2270
In 2270, an Orion vessel attacked the USS Huron for its cargo of dilithium crystals, as well as a special supply of strobolin. It was later encountered by the USS Enterprise in a field of asteroids, where it was eventually surrendered and was towed to Deneb V. (TAS: "The Pirates of Orion")
In 2381, Mistress D'Erika Tendi sent an Orion vessel to retrieve her sister D'Vana Tendi from the USS Cerritos, as per the terms of her agreement to assist the Cerritos crew in breaching the trynar shield around the Detrion system. (LD: "Old Friends, New Planets")
The final draft of the script describes the ship as "a blood-red, evil looking ship", and describes the ship's bridge as "sparser, smaller, more utilitarian than the Enterprise's."