GK2 Co-op

Online co-op for Graveyard Keeper 2. One player hosts their world, and friends join it with characters of their own.

Version 1.0. Out of beta: players have finished the whole game together with it. Back up your saves before playing all the same; they live in %USERPROFILE%\AppData\LocalLow\Lazy Bear Games\Graveyard Keeper 2. Bugs found from here on still get fixed.

Discord: join the GK2 Co-op server to find people to play with, ask questions, report bugs and hear about updates first.

Languages: the mod's menus, settings, tips and messages follow the game's language: English, German, Spanish, French, Brazilian Portuguese, Polish, Russian, Turkish, Japanese, Korean or Simplified Chinese (machine translations: tell us on the Discord if a line reads wrong).

Requirements

• Everyone needs the same game version (built for Graveyard Keeper 2 1.011) and the same mod version (the host checks both).
• BepInEx (BepInExPack 5.4.2305). The mod manager installs it for you.

Install

Install with r2modman or the Thunderstore Mod Manager and start the game modded. Every player installs it. The main menu then has a Co-op button (F8 opens the same menu, F9 its settings): if it's there, the mod is loaded.

Playing together (Steam)

Steam friends can play together with no addresses or port forwarding: the connection goes through Steam. Start the game modded (from the mod manager) with Steam running.

1. Everyone: click Co-op at the main menu. Your name starts as your Steam name: it's what the others see. Your character (inventory, money, look) is kept in the host's save under your Steam account. Connect through is set to Steam friends.
2. Host: under Host, click Host from here.
3. Partners: the host shows up under Friends hosting. Click Join <host>'s world. You wait in the host's lobby; your menu buttons stay locked meanwhile. You can also accept the host's Steam invite (host: Invite Steam friends in the Co-op menu) or use Join Game on the host's Steam profile, while your game is open at the main menu.
4. Host: start a new game or load a save. Everyone loads in together.

Or the host loads into their world first, opens Co-op from the pause menu, clicks Host this world on Steam, and partners join from their menu.

Public games, passwords and bans

Hosting options (in the Co-op menu, also while you host) decide who can join:

• Who can join: Friends (your Steam friends see your game under Friends hosting), Public (anyone with the mod finds it under Browse public games) or Invite only (only people you invite through Steam).
• Players: 2 to 8, you included.
• Ask me first: you get a yes or no question before someone comes in: for people who aren't your Steam friends (the default), for everyone, or for nobody.
• Game name, for the game browser, and an optional password. The password never leaves your PC: only a check made from it is sent.
• Other mods: which other mods joining players may run: Any, Same as mine, Approved (approve them on the Mods page) or None. Mods that change the world run in one player's game only, so the worlds drift apart. Client-side mods (what they change stays in their own player's game: HUDs, journals, trackers, frame rate) always pass, and a few mods are host-only (villagers' days, station and zombie automation): the host's copy runs them for everyone, and a player can't join with them on. The Mods page lists both.
• Non-friends may: what players who aren't your Steam friends may do: Do anything, Build, not take (no taking down buildings or taking from chests) or Only look. Trust in the Players list lifts it for a player until they leave.
• Sanity limits (on by default): other players' games only change things near their own character, earn, spend or learn no more a minute than play can, hit no harder than the game's best weapon, and can't flood your game or the chat. What's refused is undone, and you hear about it in the chat.
• Back up my save: a copy of your save before other players come in, in GK2Coop backups in the game's save folder: Before non-friends (the default), Before anyone or Never. The newest 10 are kept.
• Players may teleport: whether players may go to each other and to you: Everyone, Friends only or Nobody.

Browse public games lists public games from everywhere, with the day, players and whether there's a password. Pick one and click Join (and type its password if it has one).

To keep someone out, use Ban next to their name in the Co-op menu (unban in Settings). Bans go by Steam account, and your games no longer show up for that player. Activity in chat (Settings) shows what the others build, take down and take from chests in your world, for everyone, only you, or no one. Public games let people you don't know into your save: the mod backs it up before they come in (Back up my save), but keep your own copy too.

Over Steam, each player's character is kept in the host's save under their Steam account, so it stays theirs even if they change their name.

Playing together (IP address)

For a LAN, a virtual LAN (Tailscale, ZeroTier, Radmin VPN), or a forwarded port. Set Connect through to IP address in the Co-op menu.

1. Everyone: click Co-op at the main menu and type your name. Over an IP address your character is kept in the host's save under that name, so use the same one every time.
2. Host: under Host, click Host from here.
3. Partners: type the host's address under Join and click Join.
4. Host: start a new game or load a save.

The mod uses UDP port 8889 (you can change it in the menu). Over the internet, join the host's address on the virtual LAN, or the host forwards UDP 8889 on their router and partners join the host's public IP. Allow the game through Windows Firewall when it asks.

What co-op does

• One world, the host's. Objects, buildings, crafting stations, chests and stockpiles, graves and bodies, villagers and zombies, time and weather are all the host's, and everyone sees the same thing.
• Shared progress. Money, tech points, reputation, the tech tree, talents and inspirations, and the village's sermon buffs.
• Your own character. Inventory, carried items, energy, look and achievements are yours, kept in the host's save. Only the host's game saves.
• The story is the host's. Partners watch the host's cutscenes and scenes: from where they stand when they're close, otherwise in the host's place, and they're brought back afterwards. Story steps (talks, story objects) are the host's to do, and quest item rewards go to the host. In the intro, everyone gets their own tools.
• Work stations: one player at a time. What you make by hand goes into your bag.
• Building: partners build, take down and use the game's Move as the host does. A partner's Move shows on their screen at once, and the host's game follows when they place it.
• Fights: partners fight in the host's fight, with their HP and stamina bars and the host's wave timeline. They can carry and plant troop flags.
• Sleep: the host's bed puts everyone to sleep, and the sleep screen shows everyone's energy. A tired partner's bed asks the host. Everyone wakes once all are rested.
• The map shows everyone, and areas anyone finds are found for all.
• Shops: a partner talking to a shopkeeper gets their own shop. Vendors' stock and money are shared.
• Chat: press Enter to talk. The chat box sits in the bottom left, in the game's own style; what's said shows over the speaker's head in the game's speech bubbles, with a thought bubble while someone types. Joins and the mod's other notices show there too, and, as you like, the answers picked in conversations or every line of the story.
• The Co-op menu looks like the game's own menus. It lists everyone with their ping, lets the host remove or ban a player, bring players to them, and lets players go to each other (Teleport, if the host allows it), and has a Settings page.
• Unstuck (the pause menu, under Co-op): stuck, or fell through the map? After a yes it takes you home to the bed in your house. Falling through the map is also caught by itself: partners go back where they stood or beside the host, the host goes home.

Bugs and feedback

Report bugs in the Bugs tab of the mod's Nexus Mods page: https://www.nexusmods.com/graveyardkeeper2/mods/408?tab=bugs, or on the Discord server. Say when it happened and who was hosting, and attach both players' logs (below).

Settings and logs

• Settings: the Settings page of the Co-op menu (connection, rejoining where you left, story scene options, what new partners start with). Hover a setting's ? to see what it does. Everything else is in BepInEx/config/com.gk2coop.prototype.cfg (the file keeps its early name).
• Logs: the mod writes a detailed log to BepInEx/GK2Coop-logs. When reporting a bug, send the newest coop_*.log and BepInEx/LogOutput.log from both players, with the time it happened.