CurseForge · Minecraft mod
Simple Block Physics
Adds simple, configurable, recursive block collapse logic (i.e. block physics) to Minecraft!
Quick answer
Which Simple Block Physics release matches 1.21.1?
Simple Block Physics 1.21.1-neoforge-1.2.0 targets 1.21.1 with NeoForge. Installation on the client is optional. Installation on the dedicated server is optional. No extra mods listed for this file.
Where it goes
Is Simple Block Physics required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
The source marks this as usable on both the client and server.
What else does Simple Block Physics 1.21.1-neoforge-1.2.0 need?
1.21.1-neoforge-1.2.0 on 1.21.1. Every mod below is checked against that same setup.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add Simple Block Physics without breaking your instance.
Built for Simple Block Physics 1.21.1-neoforge-1.2.0 on 1.21.1. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 1.21.1-neoforge-1.2.0. It targets 1.21.1 with NeoForge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 1.21.1-neoforge-1.2.0. It opens that exact file at the source.
About this project
What does Simple Block Physics add?
Simple Block Physics
Adds simple, configurable, recursive block collapse logic (i.e. block physics) to your game. It does this without chunk scans or complex math, but through a 'functionally' recursive search method by assessing a block's 'support' when nearby blocks are broken.
!WARNING! Add to your world at your own risk, as it can (obviously) destroy builds!
Features
- Dramatic, dangerous cave-ins
- Realistic limits to building
- Need-based physics updates to reduce overhead
- Highly customizable config options to suit the mod to your needs
- Sky base prevention, forcing players to deal with what happens on the ground
- Pairs well with mods that add mob block breaking behavior, like Improved Mobs
Mechanics
Checked blocks lacking a support block (lower Y-level) within a thru-block search range determined by its support strength (configurable, based on hardness by default) will fall or break. Blocks are 'checked' when placed, stepped on, updated by an adjacent block being broken, or when chosen as a support by another block (configurable number of 'iterations' for this behavior, 4 by default).
Broken blocks are turned into falling block entities (like sand, configurable) which then drop, possibly break, and scatter on the ground, continuing to tumble until a suitable spot is found. Just make sure you aren't in the way when that happens!
Updates
1.1 - improved performance, added a buoyancy toggle to prevent sinking ships, and added a weight mechanic to address blocking up directly, which will disrupt pillaring and further discourage sky bases. And now ported to Neoforge for both versions!
1.2 - Added config flag for slide chance percentage, which controls how often a falling block will slide (if possible, default 80% chance) in addition to a flag to invert the indestructable blocks list, allowing you to prevent all but selected blocks from being affected by physics!
Thanks to AsianHalfSquat for the shoutout and inspiring me to push these new features!
Project description from CurseForge.
Pick your setup
Simple Block Physics by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
1.20.1
2 loader buildsCheck the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Simple Block Physics versions and loaders
1.21.1-neoforge-1.2.0
simpleblockphysics-1.21.1-neoforge-1.2.0.jar
27 Sept 2025
simpleblockphysics-forge-1.21.1-1.1.0.jar
simpleblockphysics-1.21.1-1.1.0.jar
25 Sept 2025
simpleblockphysics-neoforge-1.21.1-1.1.0.jar
simpleblockphysics-1.21.1-neoforge-1.1.0.jar
25 Sept 2025
simpleblockphysics-forge-1.21.1-1.0.jar
28 Aug 2024
Looking for an older file? The official CurseForge project page is in Resources.