Build your ship, then take it to sea
ShipCrafter is a naval sandbox combat simulator. You assemble a ship part by part from unlocked components, then send it into fights against increasingly tough opponents. The campaign runs to more than 50 missions and takes you through liberating Europe, and there is a custom battle editor for setting up your own scenarios, including weather and time of day, even pitting bots against each other.
The building side is where the game spends most of its effort. The editor shows your ship's density and center of mass as you place blocks, so you can tune the design instead of guessing. That matters because the game runs a realtime buoyancy system based on weight and submerged volume, and it accounts for ocean waves. Get the numbers right and you can build submarines with adjustable ballasts. You can also walk around your finished ship in first person view.
Combat that comes from physics, not health bars
Damage works off physics rather than health bars. Hits take out specific parts, and turrets and engines lose performance when struck, so a badly placed component can cripple a ship that looks fine on paper. Ballistics are simulated properly: shell trajectories factor in air pressure, changes in atmospheric density with altitude, and drag influenced by shell speed. Penetration is calculated from armor thickness, angle of incidence, bounce probability, and the shell's speed and mass. Armor thickness is something you choose in the editor, so your defense is a real design decision.
Be aware that speeds and distances are compressed compared to reality. The developers state plainly that hitting a target at 20km would take over a minute in real life, so combat is tuned to stay tense. Expect weather and day cycles too, including changes in wave amplitude and rain, plus a realtime fluid simulation.
Playing with friends
The campaign and ship building both support co-op, so you can work through missions together or build alongside each other. A sandbox multiplayer mode takes up to 10 players, where you can turn damage on or off depending on whether you want an actual naval battle or just to show off designs. There is also online PvP via custom battles. Manual and automatic weapon control lets you split roles, with one player driving while another aims.
Before you start, know that this is a simulation with an arcade edge: it leans realistic on physics but keeps fights readable. Modding is officially supported, and Steam Workshop is already live for sharing ships, so you can download other people's battleships, cruisers and submarines instead of designing everything from scratch.