Instant Chunks

Instead of editing blocks one at a time, Instant Chunks manipulates the native chunk data of a selected rectangular region. Copy and paste operations complete in milliseconds, and the mod is aimed at large areas, where a 20x20 block of 400 chunks is reset in under a second. Because it works on chunk data rather than iterating over blocks, it avoids the server lag that slower region tools can cause when handling big selections.

The mod suits servers that need regular resets of arenas, competitive game modes, build testing and quick restoration of destructible terrain. It is considerably faster than reloading a world from schematic files for the same purpose. The cost of this speed is a set of limits: copied chunks always keep their original elevation, and the paste point must be an integer multiple of the source's chunk offset, so fine movement by less than 16 blocks is not possible. Selections are defined by two opposite chunk coordinates given as integers, and the Y-axis range always covers the full world height.

Instant Chunks is published for Fabric only, for Minecraft 1.20.5 and 1.20.6, with 1.2.0 for 1.20.6 as the latest file. It runs server-side only, so players join without installing it. The code is released under CC0 1.0 Universal and is open source.