The Scylla
From Multiverses
The Scylla is Arethusa's Deathship/submarine.
Design
To allow it to travel in space or underwater, the Scylla is cigar-shaped. Two enormous engines are attached to the rear.
The ship is around 14km long. Six long mechanical arms can be extended from the sides.
It has many Rending Cannons, a few Lucifer Cannons and an openable bay with many Harvengers.
Its blackmetal hull allows it to go several kilometres below the surface.