Case: Zulu was a Royal Manticoran Navy alarm signal that was to be sent from a Naval vessel or installation upon good evidence that an invasion of the Star Kingdom of Manticore was imminent. The term evolved from a large-scale combat scenario developed by First Lord of the Admiralty Thomas Cazenestro in the 1530s PD, originally called "Zulu Omega". (MA2) In 1901 PD, Commander Honor Harrington sent a Case: Zulu warning through the wormhole just before shots were fired in the opening phase of the First Battle of Basilisk. (HH1)