Ratfish D is sibmarine with very simple layout. Heavy guns making it strong in battle, accessibility of everything and spacy storages. Strong engine and ballasts. Its easy to understand and maintain.
Downsides of this sub pretty noticable: no secondary armaments and no backup energy sources...
This is very good pick for a newbies and for experienced players. It can carry you through almost whole game but will lack power at the endgame.
