Create maps with World Builder

World Builder lets you create maps offline and load them on a multiplayer server. Place props, effects and areas, edit the level’s own objects, draw NPC patrol routes, and save reusable arrangements as blueprints.

Start an offline project

1. Open World Builder from the main menu.
2. Choose Kuttenberg, Trosky or Monastery, then click New project. Monastery requires its DLC. Open project loads an existing project using the level saved in that file.
3. Once the level loads, the editor opens automatically. Press F7 to switch to player control and walk around your work. Press it again to keep editing. Your project and placed objects stay in the world.

Offline access is always available; no server connection or script is needed. Return to menu ends the offline session and offers to save unsaved changes. Load last project reopens your most recently opened or saved project at its saved camera position. If the file moved, choose it again with Open project.

Place and edit objects

Use the editor’s tabs to choose what to work on:

Tab	What you can do
Library	Search the game’s prop meshes. Click a mesh to pick it up, click in the world to place it, and press Esc to stop placing.
Effects	Browse and place particle effects. Select an effect to adjust it in the Object tab.
Level	Select existing level objects to move or remove them. Del removes a selected level object; pressing it again puts it back.
Areas	Draw boxes, shapes or spheres for server scripts to use as areas.
Patrols	Draw named routes, adjust each waypoint, and preview them with a temporary NPC.
Layers	Organize props, effects and level objects, then hide or lock them while editing.
Environment	Preview the offline project under a chosen hour, sky and rain.
MCP	Let a local assistant or script inspect and control the offline editor.

Select an object and use the gizmo to move, rotate or scale it. Areas define regions; your server scripts decide what happens there. See Markers and trigger zones for area behavior and Level edits for scripting changes to existing objects.

Collision updates after scaling pauses, including grouped edits and undo. Keep proportions when collision needs to match the shape: a stretched prop uses its largest axis for collision. A model that cannot create collision reports a placement error; choose None for decoration without physics.

Control	Action
Hold right mouse	Fly using the game’s photo-mode movement keys. Change these in the game’s Controls menu.
Mouse wheel while flying	Change camera speed.
Mouse wheel otherwise	Move the camera toward or away from the point under the cursor.
Middle mouse drag	Pan the camera.
Alt + left mouse drag	Orbit the selection or the point where the drag began.
F	Frame the selection.
1, 2, 3	Move, rotate or scale with the gizmo.
G / X	Switch world/local axes or toggle snapping for the current gizmo.
Ctrl + click	Select several props or effects.
Ctrl+Z / Ctrl+Y	Undo / redo.
Hold Shift while translating	Snap props, effects, areas, area handles and patrol waypoints to the ground.

In Camera, name a view and click Remember. Selecting a saved view moves only the camera. Go to the player moves the camera to the player; Bring the player here moves the player to ground near the camera. Saved views and the current camera position stay with the project.

Esc or right-click cancels prop/effect placement even while a search field has focus. Release right mouse before holding it again to fly.

See Grid, favorites and layers for alignment, project favorite folders and locking finished parts of the scene. Use Preview light and weather to inspect the project at dusk or in rain. These controls are available in 1.6.6.

Optional: MCP integration

Enable MCP to let an AI assistant automate editor tasks, inspect your level changes, or set up a patrol preview. Your own local programs can use the same tools over HTTP without an AI agent. Follow Automate World Builder with MCP to connect, or Control World Builder over HTTP for a working PowerShell example.

Restore deleted level objects

Level > Deleted lists removed level objects even outside the nearby radius or after they stream out. Saved deletions return when you reopen the project. Search by name, class or mesh; double-click a row to frame it. Restore brings back that object while keeping its move. Include moved objects also lists objects moved without deletion. Restore all level edits undoes every level-object move and deletion, including filtered rows.

Draw areas and patrol routes

Areas support point, edge, face, radius and height handles, selection groups and editable copies of game areas. Follow Draw and edit gameplay areas to give your scripts named regions.

In Patrols, author Once, Loop or Ping pong routes with per-waypoint speed and waiting times. Follow Named patrol routes for preview controls, door behavior and deployment. Routes do not spawn NPCs until a server script creates and assigns them.

Save your project

In Project, use Save or Save as to keep an editable .project.json in a folder of your choice. Ctrl+S saves; Ctrl+Shift+S saves under another name.

The project keeps your scene, routes, groups, camera views, export settings, layers, favorite folders, viewport preferences and preview conditions. Keep it so you can continue editing after deployment.

File	Purpose
.project.json	Your editable project. Open this to continue working.
.world.json	An exported world resource for the server to load.
.blueprint.json	Reusable scene content, including selected patrol routes.

While there are unsaved changes, the editor writes a recovery copy every 30 seconds to maps/recovery.project.json beside KCDCClient.dll. Recover autosaved project opens it as an unsaved project; save it under your own name. There is only one recovery slot, shared by projects.

Use Open project for editable projects and Open blueprint for reusable content. The older Import an older map section has been removed.

Reuse groups as blueprints

1. Select props and effects with Ctrl + click.
2. In Blueprints, choose Group selection to move, rotate and scale them together. Ungroup leaves the objects in place.
3. Choose Save selection as blueprint to write a .blueprint.json.
4. In this or another project, choose Open blueprint, then Place blueprint in front of camera. Move the copy into position.

Blueprints preserve the arrangement of their props and effects. They exclude removals and moves of existing level objects, which belong to the original level. Selected routes can be included too. If an imported route ID collides with an existing one, it gets a numeric suffix; check it before wiring scripts.

Export to a multiplayer server

A world resource is a .world.json file containing objects and areas to create and patrol routes to register. It needs no loader script.

1. Save your project.
2. In Project, set Resource name to test1 and choose an Output directory with Choose export directory….
3. Click Export world resource. This writes test1.world.json in that folder. Exporting does not save your editable project.
4. Copy the export to your server folder. For a local server, you can export directly into that folder.
5. Merge these settings into the existing mod object in server.json:

server.json

{
  "mod": {
    "level": "kutnohorsko",
    "world_resources": ["test1.world.json"]
  }
}

This example uses Kuttenberg. Set level to match your project: kutnohorsko for Kuttenberg, trosecko for Trosky, or klaster for Monastery. Keep your other server settings and any existing entries in world_resources.

Paths are relative to the server’s working directory, normally the server folder. If you copy the file into worlds/, use worlds/test1.world.json. Restart the server after adding or replacing an export. The server creates the content and sends its world state to joining players. Props and effects appear as players come within streaming range; level edits reach every player.

To publish changes, reopen the project, edit, save, export again, copy the updated file to the server and restart it. Server scripts can use the exported areas and objects; changes made while the server runs are not saved back to your project or export. See Use World Builder exports in scripts to wait for loading and find its areas, objects and routes. The village patrol tutorial combines an exported scene with a script-owned guard.

For a few objects that belong in a script, select them and choose Copy selection as API calls, then paste the calls into a server resource. This copies only the selection. Areas has Copy selected areas as API calls, and Patrols has Copy API call for its selected route.

Allow building in multiplayer

Access starts disabled for each multiplayer connection. In a server script, call player.setWorldBuilderEnabled(true) for a player who may build. They can then press F7. Calling player.setWorldBuilderEnabled(false) revokes access and closes their editor. Access resets when they disconnect.

The sample game mode provides /builder (also /builder on) and /builder off. These are test commands available to everyone in that sample. Your own game mode should decide who may build. The old server-wide mod.map_editor setting is no longer used.

Client scripts can also call MapEditor.open(), which returns "opened", "alreadyOpen" or "disabled". MapEditor.isEnabled() checks access, MapEditor.isOpen() checks whether the editor is open, and MapEditor.close() closes it. While it is open, it holds the free camera, so NoClip cannot use it.

Editing during multiplayer changes the builder’s local scene. To share those changes with everyone, export and deploy them using the steps above.

If something does not work

Problem	Check
F7 does nothing in multiplayer	Your server script must grant access for this connection. Close chat or other screens that hold the controls, then try from gameplay.
The server reports an unknown mod.world_resources key	Update to a server build supporting world exports, and use a compatible client.
The server refuses to load an export	Read the startup error. Check the path, file format and project level. Use the exported .world.json, not the editable project.
Other players cannot see your changes	Export again, copy the updated file to the configured path and restart the server. Saving a project alone does not deploy it.

See server.json settings for loading several exports or assigning resource names.

Offline character vitals

Offline World Builder protects your character’s vitals while you build. On a multiplayer server, the server’s rules still apply.