Blue 3 – Marcot
- Country of Origin: France
- Color(s): Green, Black
- Status after the OVA: Unknown; Possibly scuttled
The French-built Blue 3 (Marcot) played a key role in Blue Fleet’s victory over the Ghost-Ship. Acting as a decoy, its actions allowed Blue 6 to attack the Ghost-Ship from above i.e. its blind spot. This victory was of course partly due to the overconfidence and recklessness of Verg.
It is not known what happened to the Marcot and its crew at the end of the anime. The sub was already badly damaged and could only crawl along the ocean surface. It was probably scuttled and its crew rescued/transferred to Blue 6.