Copycat Mimic Optional for Observer Effect observereffect-1.0.0.jar
optionalMatching file found Matched file: Copycat v1.2.5
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CurseForge · Minecraft mod
Observer Effect
Observer Effect changes the world when nobody is looking. Blocks shift, rooms alter, and strange growths appear, making the environment feel alive and unpredictable.
Choose a version Pick your version below, then grab the matching file.
Quick answer
Which Observer Effect release should I use?
Latest stable file observereffect-1.0.0.jar
Game version 1.20.1
Loader Forge
Observer Effect observereffect-1.0.0.jar targets 1.20.1 with Forge. 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 Observer Effect 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 Forge
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.
What else does Observer Effect observereffect-1.0.0.jar need?
observereffect-1.0.0.jar. Change the file and its required mods may change too.
This file does not list any required mods. Do not add a library just because a different file uses it.
We only count dependency files that match this setup. A file for another loader does not fill the gap.
Before you install it
Add Observer Effect without breaking your instance.
Built for Observer Effect observereffect-1.0.0.jar. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use observereffect-1.0.0.jar. It targets 1.20.1 with Forge; 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 observereffect-1.0.0.jar. It opens that exact file at the source.
About this project
What does Observer Effect add?
The world behaves differently when unobserved.
Turn away for a moment and things begin to change. A wall isn't where you remember it. A room seems larger. Trees twist into impossible shapes.
The longer you play, the harder it becomes to trust what stays the same.
Project description from CurseForge.
Pick your setup
Observer Effect by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
Minecraft version
1.20.1
1 loader buildCheck the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Observer Effect versions and loaders
observereffect-1.0.0.jar
12 Jun 2026
Client Source doesn’t say Server Source doesn’t say Dependencies No extras listed Listed on Release listing
Check the 1.20.1 · Forge setup 1.20.1Forge release
Looking for an older file? The official CurseForge project page is in Resources.
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