MCA Selector vs Nibnya

MCA Selector is a free tool for selecting and modifying chunks and regions in Minecraft Java Edition world saves. It can export, delete, or edit selected areas using filters such as data version, last update time, and inhabited time; multiple conditions can be chained. Custom one-line Groovy scripts and a Script Editor extend filtering. The chunk editor exposes the full NBT structure, including points of interest and entity data, allowing tags to be changed, added, deleted, or moved. Users can import chunks from another world with offsets and overwrite options, and copy or paste selections through the system clipboard.

Customizable color-gradient overlays show per-chunk values. A command-line mode handles operations including selection creation, chunk import and export, deletion, region defragmentation, NBT changes, and image generation. Downloads include Windows, macOS, and Linux builds, plus a universal JAR. MCA Selector supports Anvil .mca region files. The project warns that snapshot-generated worlds may not work even when a version appears in its support table, and recommends backing up worlds because the tool can modify or delete chunks.

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