And now let us mention some of the vehicle`s in the game. First we have our 1 man submersible called Seamoth. It`s simple as it gets, with a bubble looking cabin for you to feel comfortable. It had 4 upgrade slots which 1 of them will probably be taken by depth module. At first seamoth can travel up to 200m in depth, depth module mk1 can bring you down aditional 100m, that makes it 300m in total. Mk2 brings you down 500m and mk3 900m. Now to progress farther in game you are going to have to go deeper where makes seamoth useless in deep waters. That`s why there is our good ol` pal cyclops. It`s supposted to be manned with 3-4 people, and multiplayer was supposted to be an option in Subnautica, but developers stopped working on it, making you alone in cyclops. Cyclops has 6 upgrade slots, and again 1 will be taken by depth module. And couple of important ones you`ll probably be using are fire supresion system, shield and sonar. I didn`t mention this but Seamoth has 1 powercell powering it up, while cyclops has 6, so be sure to store a lot of powercells before long exploration, or in case you want to fight leaviathans, because shield generator drains a lot of power. Cyclops can also be used as a mobile base, as it has a lot of space and you can put a lot of thing in it. And last but not least we have prawn suit. Prawn suit will be most important later in the game. Beside 4 upgrade slots, it also has 2 arm slots, meaning you can switch arms on it. People usualy go with a drill arm and graple arms, as mobility without graple is low, and drill arm is needed to mine deposits of materials that are important, or just to grind them up fast. With depth module mk3 he can go down up to 1700m which is more than enough to make him be anywhere in the game, except too deep in the void or as I said earlier, the dead zone.