- Jarok's scout ship
- Lovok's warbird
- Mirok's science ship
- Narissa's ship
- Oh's warbird
- Sela's warbird
- Tebok's warbird
- Tomalak's warbird
- Vreenak's shuttle
- Unnamed D7-class starships
- Unnamed Romulan Birds-of-Prey (22nd century)
- Unnamed Romulan Birds-of-Prey (23rd century)
- Unnamed Romulan warbirds
By unnamed class
In 2364, a contingent of seven battle cruisers converged on a Federation border outpost. While the outpost called for reinforcements from the nearby USS Berlin and USS Enterprise-D, the encounter ended without incident. (TNG: "Angel One")
According to the ship's captain, they had intercepted several communiques between the Yridians and Cardassia. He was later present, while under cloak, when Professor Galen's shuttlecraft was attacked.
As the USS Enterprise-D picked up the mission where Galen left off, this ship shadowed the Enterprise, eventually arriving at Vilmor II, where the captain and a few of his crew surprised the Cardassian, Klingon, and Federation delegations that were present there, as they were attempting to discover the secret of the genetic codes that led them to the planet.
In 2365, Captain Donald Varley recorded a personal log aboard the USS Yamato stating that they had "been spotted by a Romulan cruiser, but after playing hide and seek through several solar systems" he thought they had lost them. (TNG: "Contagion")
In 2346, several of these patrol ships, presumed to be Romulan Warbirds, attacked the Klingon colony on Khitomer after having received the defense access code from the outpost. These ships were able to lower the outpost's shields, and destroyed the outpost.
Twenty years later, one of these ships was captured, and contained the logs that provided new information to the Klingon High Command on the Khitomer attack. These logs, according to Data, "clearly indicate a transmission from the outpost to the Romulans moments before the shields dropped." The High Command had learned of the treachery, but according to K'mpec, "only the council knew whose security code had been transmitted. Ja'rod, father of Duras."
Since the House of Duras was powerful, according to K'mpec, "if the truth were known, it would shatter the council, almost certainly plunge us into civil war." Because "someone had to be blamed," the Council revealed that Mogh was responsible for the treason, and since Worf was in Starfleet, they "did not expect [him] to challenge the judgment." (TNG: "Sins of the Father", "Redemption")