The Eagle-class frigate Kay and her sister ship FWLS Bors were both constructed to be escort vessels for the fifth WarShip of the Thera-class of carriers being built by the Free Worlds League, the FWLS Delos, which was due to enter active service in 3078.
The Word of Blake suborned the Bors during the opening stages of the Jihad and fought in the Blakist cause for several years before being destroyed in one of the series of battles fought between the Blakists and the Draconis Combine and Clan Nova Cat in the Benjamin system in 3072. The Delos joined the Principality of Regulus as the League fragmented, becoming the RPS Delos, while the Kay was destroyed in 3068 by the Blakists.
- The Kay appears to have been named for a figure associated with the myths around the 5th or 6th century AD King Arthur; in this case, one of the Knights of the Round Table, Sir Kay.
- The destruction of the Kay and seven other Free Worlds League WarShips unaccounted for specifically by name in sourcebooks was confirmed by the BattleTech Developer Øystein Tvedten via the Catalyst Game Labs Ask The Writers Forum:
|“|| Delphi (Thera-Class) - Destroyed by Word of Blake, 3068
Thessaly (Thera-Class) - never completed, scuttled in dock by loyalists to keep it out of Blakists' hands in 3068
|— Øystein Tvedten, 07 December 2013|
- Field Manual: Updates, p. 144, "Ships Of The FWL"
- Jihad: Final Reckoning, p. 128, "Captured Ships"
- Jihad: Final Reckoning, p. 22-23, "Only Way To Be Sure"
- BattleTech Devloper confirms the destruction of the Kay