The submarine-launched ballistic missile was a type of ballistic cruise missile operated during the Usean coup d'état of 1998.
Usean coup d'état
During the Usean coup d'état, the Usean Rebel Forces seized two Dragonet-class submarines from the Allied Forces; the Fensalir and the Folkvangr. Both submarines were equipped with ballistic missiles and posed a great threat to the civilian population as well as the Allied Forces if they were to be used.
The Fensalir was discovered as it was sinking Allied Forces vessels in the waters surrounding Seals Bridge. It had not utilized an ballistic missile at that point, but the Allied Forces could not risk the use of the weapon, so they ordered Scarface One to destroy the submarine and the ballistic missiles with it.
The Folkvangr was not discovered until a couple of hours after Saint Ark was liberated from the Rebel Forces late in the war. It surfaced and prepared to launch a ballistic missile at the city. Scarface One was ordered to destroy the submarine before it could launch a ballistic missile. The submarine was destroyed, but it did manage to launch a ballistic missile with improved speed and the ability to evade attacks like a standard fighter. Scarface One chased down the ballistic missile, which was closing in on St. Ark, and managed to destroy it before it hit the city.