I wanted to learn more about the wiring mechanics of Barotrauma, so I decided to make my own submarine. Just a single room with the bare minimum necessary to make it a functioning sub.
At first I thought it might be fun if the only way to steer the sub was to manually set the engine and ballast pump speed, but I quickly discovered that such a small sub reacts very strongly to small changes to the ballast and it would be really difficult to just have the sub stay at a particular elevation. You'd basically have to bounce from the floor to the top or do almost blind hops.
Now, normally you'd hook the engine and ballast pump up to a navigation terminal, which looks like this:
You can either use the autopilot and just click wherever you want your sub to be or you can manually steer and click the direction your sub should accelerate towards and the terminal automatically controls the engine and ballast pump.
However, that seemed too boring to me, so instead I set up three different modes for both the engine and the ballast pump: off, forward/up and backward/down. I then set up a button for the engine and another for the pump that would cycle through these modes when pressed. Note that submarines have quite a lot of inertia, so the 'off' mode does not mean that the sub stops moving, it just means it stops accelerating.
It's a bit tricky to control, but it honestly worked a lot better than I expected. Just look at this perfect docking maneuver:
View: https://www.youtube.com/watch?v=L1mV6iMRWGs
And because I have no reactor and the engine only runs on a max of 10% power the sub is quiet enough to pass by most enemies without being noticed. Of course, if I do get noticed I have a problem since I have no turrets on the ship. Luckily I'm not entirely without options. If I'm close enough to the outpost I can try to rush there while the bots keep the hull intact enough to prevent us from sinking (worked once, failed once). If something comes in I can try to shoot it before it kills us (worked a couple of times, failed a couple of times, also shot my bots quite a few times). Or I can simply try to squash the enemy between the sub and a cavern wall (worked twice):
View: https://www.youtube.com/watch?v=Nbwwx5sR7Qo
I did a few missions like this and while I had to retry some of them, sometimes twice, the sub worked remarkably well. The low engine power helps prevent major damage when I do ram a cavern wall (which happens fairly frequently) and the bots repair any leaks in a couple of seconds usually.
Still, the game is a lot more fun when playing with friends compared to playing alone. The bots are too good at what they do and there's a distinct lack of chaotic energy you get when a bunch of real people start panicking when things go wrong.