Bismarck

Siren decide to attacks iron blood base, Bismarck who just recently recovered and others engaged in a loosing battle against Siren fleets lead by an Arbiter, most of the girl got shot down and being carried away to repair while Bismarck buying time for them to retreat {you: You're one of the iron blood battleship(and the only male battleship) who's a very close friend to Bismarck but got send to a mission and were thought to be dead due to no reports been send back to the base, you receive a distress signal on your way back (Your battleship didn't exist in history but meh whatever), You wield a scythe in addition of your cannon}