Nether Bedrock Cracker Mod (26.2, 1.20.1) – Cracking Nether World Seed from Bedrock Patterns

Nether Bedrock Cracker Mod helps players crack the seed of the Nether world based on bedrock patterns without admin privileges, or to explore Nether structures more easily. It works by analyzing the positions of bedrock blocks in the Nether, which depend on the seed starting from version 1.18 (when Mojang changed the bedrock generation mechanism to be seed-dependent).

Features:

• Quickly find the seed to use tools like Chunkbase or Amidst, helping locate Nether Fortresses, Bastion Remnants, or other structures.
• Suitable for technical Minecraft players, seed hunting, or on SMP servers where the seed is hidden.
• Can crack either the world seed or structure seed, depending on the configuration.
• Requires manual collection of bedrock data (positions), and the cracking process may take time (from minutes to hours, depending on data quantity).
• Does not work if the Nether seed is manually set (not following the game’s rules).

How to use:

Collect Bedrock Data

• Enter the Nether (using a portal).
• Find and record the coordinates (x, y, z) of bedrock blocks at y=4 (floor) and y=123 (ceiling). Bedrock here is rarer (1/5 chance), so each block provides more information.
• Collect from both floor and ceiling for accurate results (at least 20-28 blocks to crack a 64-bit seed, based on RNG calculations).
• Coordinates x, z don’t need to match; any position works as long as it’s in a loaded chunk.
• Use F3 to view coordinates. Record in a text file (e.g., each line as x y z).

Run the Mod In-Game

• Main command: /nbc:crack [<threads>] [<bedrockgeneration>] [<outputmode>]
  • threads: Number of CPU threads (default: all available threads for speed).
  • bedrockgeneration: NORMAL (default, for vanilla/newer Paper) or PAPER1_18 (for older Paper with columnar bedrock bug).
  • outputmode: WORLD_SEED (default, world seed) or STRUCTURE_SEED (if world seed isn’t found).
• The mod uses collected bedrock data to crack the seed. Results appear in chat or GUI (if available).
• If using an external tool (not the mod): Run the executable from GitHub 19MisterX98/Nether_Bedrock_Cracker, load the data file, and view results in the GUI or output file.

View Results

• If successful, you get a seed (a long number). Use it in tools like Chunkbase Nether Fortress Finder to view the map.
• If no seed is found: Collect more bedrock, try a different mode, or check if the server uses a custom seed.

Example Usage

• Suppose you collect bedrock at: (10, 4, 16), (20, 123, 30), etc.
• Run /nbc:crack 4 NORMAL WORLD_SEED (using 4 threads).
• The mod processes and outputs a seed like 1234567890123456789.
• Note: On servers, the mod may be detected by anti-cheat; some servers block it by altering structure seeds.

Important:

You need to have Java 23 installed to use this mod. I recommend to get Java 23 from adoptium.net. Next, configure your Minecraft launcher to use this release of Java.

• Vanilla launcher: Go to Installations -> Edit -> More options -> Java executable.
• MultiMC: Go to Edit Instance -> Settings -> Java -> Java Installation.
• PrismLauncher: Go to Settings -> Java -> Java Runtime -> Auto-Detect....
  • Do not forget to enable “Skip Java compatibility checks”.

If you run into issues, contact your launcher’s support.

Nether Bedrock Cracker Mod Download Links