Minecraft 1.21.9 Snapshot 25w31a – Copper Golem, Chests & F3 Overhaul

Minecraft 1.21.9 Snapshot 25w31a marks the beginning of the Fall 2025 update cycle with one of the most content-packed snapshots to date. This version introduces the Copper Golem, Copper Chests, oxidizable tools and lightning rods, functional Shelves, and a revamped F3 debug interface. Together, these additions significantly expand redstone automation, storage systems, and gameplay personalization for survival and technical players alike.

Features:

Copper Golem

• How to create: Place a Jack o’Lantern or carved Pumpkin on top of a Copper Block.
• Behavior:
  • Gradually oxidizes like copper blocks.
  • Can be waxed to preserve its current oxidation state.
  • When fully oxidized and not waxed, transforms into a Copper Golem Statue Block.
  • Can pick up to 16 items from nearby Copper Chests and sort them into regular or trapped chests based on item type.

Copper Chests

• A brand-new chest type with four oxidation stages (like other copper blocks).
• Can be waxed to lock its oxidation level.
• Crafted using 8 Copper Ingots around a regular chest.
• Works with Copper Golems for automated sorting.

Shelves (Storage + Redstone)

• Can hold up to 3 item stacks visibly on its front.
• Connects horizontally (up to 3 blocks) and interacts with your hotbar using Redstone power:
  • 1 shelf = 3 rightmost hotbar slots
  • 2 shelves = 6 rightmost slots
  • 3 shelves = entire hotbar
• Crafted using 6 Stripped Logs from any wood type.

Oxidizable Lightning Rods

• Now made from Copper, these rods also oxidize over time.
• Add more depth and progression to lightning redirection in survival.

Copper Armor, Tools & Horse Armor

• New equipment tier: Copper.
• Tools, weapons, armor, and horse armor are now craftable using copper.
• Behave similarly to iron gear but with oxidation states and visual variety.

Technical Changes:

• Debug/F3 Screen Overhaul:
  • Access new settings via F3 + F5 to customize what debug info is shown (e.g., FPS, coordinates, entity hitboxes).
  • Option to keep debug info always visible.
  • Added Octree visualization, chunk borders, and more for technical players.
  • Settings now persist between sessions.
• Chunk Loading Improvements:
  • Removed the outdated “fixed chunks”/spawn chunks mechanic.
  • Players now use more reliable methods for loading chunks like Nether portals or Ender pearls.
  • Added a chunk loading progress bar back to the loading screen (removed since version 12w18a).
• Performance Enhancements:
  • Improved chunk data transmission for players with slow or unstable internet.
  • Addressed various long-standing F3 interface bugs, rendering issues, and audio glitches.

Screenshots:

Experimental features

New controls

Loading worlds

New armor

New tools

Copper nuggets

Horse armor

Shelf block

New f3 screen

Copper golems

Copper statues

New lightning rods

Requires:

Java 21+

Java Runtime Environment

How to install:

• Please visit the following link for full instructions: How To Download & Install Minecraft Snapshots

Why use Minecraft 1.21.9 Snapshot 25w31a?

This snapshot is ideal for players who enjoy:

• Building automation systems using redstone mechanics and new shelf-hotbar interactions.
• Expanding their survival base with functional and decorative Copper Golems and Copper Chests.
• Exploring the early stages of Minecraft’s next major update, complete with powerful new debug tools, chunk optimization, and customizable UI.
• Embracing a more immersive gameplay experience with oxidizable gear and visual progression systems.

Whether you’re a technical player or a builder looking to modernize your tools and base, this snapshot opens up a rich sandbox of possibilities.