Axion Project

The hotbar-driven building toolkit for Minecraft — live in-world previews, terrain editing, and multiplayer-ready edits

Axion is an open-source Minecraft building toolkit. The mod provides hotbar-driven editing tools and live in-world previews; the matching Paper plugin applies and validates those edits on multiplayer servers. Axion ships for both Fabric and NeoForge, so pick the edition that matches your loader.

Key Features

• Hotbar Editing Tools Move, clone, stack, smear, erase, extrude, and mirror terrain directly from the hotbar.

• Live In-World Previews Preview edits before confirming them, including large GPU-rendered selections that show exactly what will be written.

• Magic Select Select organic regions with masks, templates, and a searchable block picker.

• Building Utilities Use symmetry, saved hotbars, replace mode, infinite reach, no-clip, and other creative building helpers.

• Capabilities Toggleable tools that change how blocks are placed and reacted to:

  • Phantom — walk over tripwire, pressure plates, sculk sensors, redstone ore, cobwebs, and big dripleaf without triggering them.
  • No Updates — suppress neighbour notifications so gravity blocks stay put, redstone does not re-evaluate, and fluids do not flow.
  • Force Place — place a block where a player or mob is standing and ignore support rules (lanterns hang under lanterns, redstone sits on redstone).
  • Angel Placement — place blocks in mid-air four blocks in front of the camera, with a ghost showing where the next click lands.

• Undo & Redo Reverse edits locally or through the companion Paper plugin.

Subtle Changes

• NeoForge Support Axion now publishes a native NeoForge edition alongside Fabric, covering 1.21.6 - 1.21.11. NeoForge bundles its own Kotlin runtime, so no separate language mod is required.
• Fabric Requirements The Fabric edition needs Fabric API and Fabric Language Kotlin installed alongside the Axion jar.
• Multiplayer Authority On Paper servers, builders run the Axion mod client-side while the server runs the matching Axion Paper jar, keeping edits authoritative and policy-aware.
• Version Coupling The Fabric mod and the Paper plugin share a network protocol revision and must be updated together; a mismatch refuses server-backed editing.
• Java 25 Minecraft 26.1 / 26.2 builds require Java 25 and ship as separate artifacts because their rendering APIs differ.

Supported Loaders & Minecraft Versions

Release artifacts are grouped into compatibility ranges:

1.21 - 1.21.1
1.21.2 - 1.21.3
1.21.4
1.21.5
1.21.6 - 1.21.8      (Fabric + NeoForge)
1.21.9 - 1.21.11     (Fabric + NeoForge)
26.1 - 26.1.2
26.2

Choose the jar whose filename matches the Minecraft version range you run, and keep the mod and plugin on the same Axion version.

Download

⬇ Download the latest Axion jars here.

Each supported range has a Fabric mod jar and a matching Paper plugin jar; a Fabric dedicated-server jar is published for 1.21.11. NeoForge jars are provided for the 1.21.6 - 1.21.11 ranges.

Installation

For singleplayer, install the Axion jar for your loader together with its requirements:

• Fabric — Axion + Fabric API + Fabric Language Kotlin.
• NeoForge — Axion only (Kotlin is bundled).

For a Paper server:

1. Install the matching Axion mod on each builder's client (Fabric or NeoForge).
2. Install the matching Axion Paper jar in the server's plugins directory.
3. Restart the server and grant the required Axion permissions.

See the wiki for server configuration and permissions.

Documentation

For usage instructions, see the official Axion Wiki.

Support

• 📖 Wiki - Learn how Axion works. Contains answers to most questions.
• Issue Tracker - Report problems or bugs on the issue tracker. Check if someone else reported your issue before posting.
• GitHub Discussions - New ideas, feature requests, or other general discussions.
• Discord Community

Companion Plugin

Axion's multiplayer editing is enforced by the Axion Paper plugin, which validates and applies edits on the server. The mod and plugin must stay on the same Axion version.

Axion is licensed under the GPL-3.0 license.