The Type XI is a German anti-anti-submarine-submarine. It is armed with two batteries of 128mm guns, meant to engage escort ships, which would be woefully outgunned. Furthermore, it carries an Arado Ar 231 reconnaissance seaplane. The Type XI was produced during the Second Weltkrieg, meant to wage submarine warfare against the western powers, but such an occasion never materialised. A quarter of those produced ended up in Oceanyka through arms sales, where it has found new life; the Type XI is very adept at close-range carronade ambushes, from which even capital ships should be careful.
As a cruiser submarine, the Type XI can engage ships with far cheaper cannon shot, as well as bomb surface targets. In a close range ambush, it will decimate even fairly heavily armoured ships. However, as it must surface to fire, it will become vulnerable to returning shots, as submarines are unarmoured.