SailingTogether

A BepInEx mod for Valheim that adds cooperative rowing. In vanilla, only the player at the helm can move the ship. With SailingTogether, every player sitting on a ship bench can row with W (forward) and S (backward) instead of standing up. Jump still stands you up.

Requirements

BepInEx is required. SailingTogether is a BepInEx plugin and does nothing without it.

• Valheim (Steam)
• BepInExPack Valheim (BepInEx 5.4.x) installed in the game folder
• Every player on the ship must have the mod installed (see Multiplayer)

Installation

Thunderstore / r2modman (recommended): install SailingTogether from the mod manager — BepInExPack Valheim is installed automatically as a dependency.

Nexus Mods / Vortex: download the main file and install it with Vortex (BepInEx must already be installed).

Manual:

1. Install BepInExPack Valheim and run the game once, so the BepInEx folder is created.
2. Download SailingTogether-<version>.zip from Releases and extract it into the Valheim folder (it contains BepInEx/plugins/SailingTogether/SailingTogether.dll).
3. Start the game. The log (BepInEx\LogOutput.log) should show SailingTogether 1.0.0 loaded.

How it works

• Rowing works when the ship is at speed 1 (oars). It also works in reverse (RowInBack) and, optionally, while stopped (RowInStop, which also allows rowing with nobody at the helm).

• Each rower pushes on the side of the ship they are sitting on:

  Port (left)	Starboard (right)	Result
  W	W	goes straight, faster
  W	—	turns right
  —	W	turns left
  W	S	spins in place to the right
  S	S	brakes / goes backward

• A bench on the ship's centerline (CenterDeadZone) only pushes, it does not turn the ship.

• The helmsman keeps full control of speed and rudder; the rowers' force is added on top.

Ship HUD

A top-down view of the ship (bow up) in the lower-right corner, built from the game's own sprites: ship_top (the orange boat from the wind indicator), winddirection (the wind arrow) and ship_rudder_icon (the oar).

• Helmsman: every bench — grey ring = free, blue = player, purple = simulated (debug panel).
• Rower: the ship and only your own bench (gold).
• Each occupied bench shows an upright oar that sways like the vanilla helm oar: short and quick when rowing forward (W), wider and slower when rowing backward (S), still when idle.
• A green (W) or red (S) arrow outside the hull, next to each rowing bench.
• The helm is shown in yellow (filled when someone is steering). Oars and arrows turn grey when the current speed does not allow rowing.

Debug simulator (optional)

For testing alone. Disabled by default — enable it with [Debug] SimulatorPanel = true.

Press F8 on board a ship: the panel lists the ship's real benches (bow to stern, with the detected side), each with a -1 (S) / 0 / 1 (W) slider, plus shortcuts (all W/S, left W, right W, spin, reset).

1. Take the helm and set speed 1.
2. Press F8, set the benches, press F8 again to close. The simulated rowers keep rowing while you steer.
3. While the simulation is active, a status line shows rowers, thrust, turn, speed, yaw rate and whether force is being applied.

While the panel is open the cursor is free and character input is blocked.

Multiplayer

Ship physics only runs on the ship's owner (the client simulating it). Each rower writes their input into their own Player ZDO (synced automatically by the game) and the owner reads and applies it — no extra RPCs. All players need the mod. The force/turn values used are the ones from the config of whoever currently owns the ship.

Configuration

BepInEx\config\farias.SailingTogether.cfg (created on first run):

Building from source

Requires the .NET SDK. BepInEx must be installed in the game folder, because the project references BepInEx.dll and 0Harmony.dll from <Valheim>\BepInEx\core and the game assemblies from <Valheim>\valheim_Data\Managed.

dotnet build -c Release -p:GamePath="C:\Path\To\Valheim"

The DLL is copied to <Valheim>\BepInEx\plugins\SailingTogether\ after the build. Use -p:DeployToGame=false to skip copying.

To build the release packages into dist/:

dotnet build -c Release -t:Package -p:DeployToGame=false

The version lives in SailingTogether.csproj (<Version>) and must match SailingTogetherPlugin.ModVersion — the Package target fails if they differ.

Support

If you enjoy this mod, consider buying me a coffee:

https://buymeacoffee.com/chrystianfarias

License

SailingTogether — Copyright (c) 2025 Chrystian Farias.

Licensed under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0). You may share and adapt this work with attribution, for non-commercial purposes only. See LICENSE for the full text.

Third-party

• BepInEx — github.com/BepInEx/BepInEx, licensed under the GNU Lesser General Public License v2.1 (LGPL-2.1). BepInEx is not included in this repository or in the mod release; it must be installed separately.
• HarmonyX (shipped with BepInEx) — MIT License.
• Valheim and its assets are the property of Iron Gate AB. This project is not affiliated with or endorsed by Iron Gate or Coffee Stain. No game assets are included: the HUD sprites are loaded from the installed game at runtime.