World Importer

The mod is used to copy terrain from a separate save into the current one. The source is a local world's region folder containing MCA files, and the chunks in that folder are written over the matching chunks on the target world. Because existing chunks are overwritten, the mod suits areas where nothing has been built yet, or where the existing builds can be replaced. The author recommends making a backup before pasting.

The mod is installed on both the client and the server, and it works on Fabric, Forge and NeoForge. Its upload settings are reached by pressing the K key, which opens a configuration screen; with Mod Menu on Fabric, that screen is also accessible from the Mod Menu list. Commands used by the import require operator permissions at level 2. Files are published for 1.19 – 1.20.6 under the MIT License, and the code is open source.

Once an import finishes, lighting is recalculated and the affected chunks are updated and synced to players. During the upload, the top of the screen shows progress. Upload pace follows a configured interval, and automatic throttling lowers the rate when the server's ticks per second drop, with the maximum interval capped at 40 ticks.