CurseForge · Minecraft mod

Mechanic Rollback

Brings back Java mechanics removed or changed in 1.21.9-26.3: spawn chunks, old Mining Fatigue, shield knockback and arrow-proof endermen in boats. Server-side, every feature togglable.

Choose a version Pick your version below, then grab the matching file.

Quick answer

Which Mechanic Rollback release matches 26.3?

Updated last month

Best match for your filters vanillarestore-1.0.0.jar

Game version 26.3

Loader Fabric

Mechanic Rollback vanillarestore-1.0.0.jar targets 26.3 with Fabric. The project page does not say whether this file belongs on the client, dedicated server, or both. No extra mods listed for this file.

Where it goes

Is Mechanic Rollback required on the client, server, or both?

The project page does not say whether this file belongs on the client, dedicated server, or both.

Client Source doesn’t say

Dedicated server Source doesn’t say

Loader for this release Fabric

Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume

The source does not explicitly classify this release as client-only or server-only.

Understand client and server requirements Read the Minecraft installation guide

What else does Mechanic Rollback vanillarestore-1.0.0.jar need?

vanillarestore-1.0.0.jar on 26.3. Every mod below is checked against that same setup.

No extra mods listed for this file

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 Mechanic Rollback without breaking your instance.

Built for Mechanic Rollback vanillarestore-1.0.0.jar on 26.3. Pick another file and the loader, install side or required mods may change.

01
Stick to this file

Use vanillarestore-1.0.0.jar. It targets 26.3 with Fabric; 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

The project page does not say whether this file belongs on the client, dedicated server, or both.
04
Pick the file you checked

Use the “Get this file” button beside vanillarestore-1.0.0.jar. It opens that exact file at the source.

About this project

What does Mechanic Rollback add?

Mechanic Rollback brings back Java Edition mechanics that recent updates changed or removed. Each feature can be switched off on its own. There are no dependencies, and Fabric API is not needed. The mod is server-side: drop it into your server's mods folder and players can join without installing anything.

What it restores

Feature	Removed / changed in	Config key
Spawn chunks: the chunks around world spawn stay loaded and keep ticking with nobody nearby, like before. The radius works like the old `spawnChunkRadius` game rule (default 2).	1.21.9	`spawnChunks`, `spawnChunkRadius`
Old Mining Fatigue: Mining Fatigue III (Elder Guardians) is back to its old strength. It was 10x weaker in 26.3.	26.3	`legacyMiningFatigue`
Shield knockback: a hit that is fully blocked by a shield knocks the blocker back again.	26.3	`shieldKnockback`
Endermen in boats/minecarts dodge projectiles again, so enderman holding cells and farms keep working.	26.3	`endermanProjectileImmunity`

Configuration

config/vanillarestore.json is created on first start. Set any option to false to get the current vanilla behaviour. Restart the server after editing.

{
  "spawnChunks": true,
  "spawnChunkRadius": 2,
  "legacyMiningFatigue": true,
  "shieldKnockback": true,
  "endermanProjectileImmunity": true
}

Notes

Mining speed is also predicted by the client. If only the server has the mod, players mining under Mining Fatigue III may see blocks break and then reappear. Install the mod on the client as well for smooth mining.
Works in singleplayer too (install it on the client).
Attribute swapping and the MC-101770 projectile redirection are still in vanilla 26.3, so this version does not change them. If Mojang removes them, a future update will bring them back.

Compatibility

Minecraft 26.3, Fabric Loader 0.19.5+, Java 25.

Project description from CurseForge.

Pick your setup