Preparing Your Modpack

Overview

Cleanroom Loader is compatible with the vast majority of Forge mods and will usually run them without issue.
However, some mods remain deprecated, redundant, or outright incompatible—either because they’ve been superseded by better alternatives or because they introduce critical problems.
To prepare your modpack for Cleanroom Loader, review the lists below and make replacements where necessary.

Note

Pro tip: if you seek to automate this process, you can build/update your pack using the Barebones Template, which is a minimalist optimization template. It includes PackCompanion, a runtime analysis tool that scans your actual modlist and generates a personalized report flagging problematic or deprecated mods, complete with custom scripts to cleanly remove them from your instance.

Incompatible / Problematic Mods on Cleanroom Launcher

Mod	Reason	Action
AdvancedShader	Binary patching, incompatible.	🚫 Remove
Essential.gg	Patched but causes many issues.	✅ Use Lan UPNP (Non-Proxy option) or E4MC Retro (Proxy Option)
FoamFix	Outdated and prone to cause issues in Cleanroom Environment	✅ Use VintageFix
Mouse Tweaks	Outdated and prone to cause issues	✅ Use Mouse Tweaks Unofficial
Phosphor	Incompatible	✅ Use Alfheim Lighting Engine / Hesperus
Polyfrost series	Awaiting official fixes.	—
Raw Input	Already included in Cleanroom.	🚫 Remove
Secret Rooms	Has an issue with updater	🚫 Disable the update checker in config file
SerializationIsBad	Redundant. Modern Java versions fix the issue this solves	🚫 Remove
TexFix	Merged and rewritten in Chibi	✅ Use Chibi
VanillaFix	Merged and improved in Chibi	✅ Use Chibi
Sound Physics	ASM incompat	✅ Use Sound Physics Remixin
Custom Loading Screen	Incompat with new GSON	✅ Use the build from this issue page
UltimateStack	ASM incompat	✅ StackUp! should replace it in most cases.
The One Probe	Unmaintained	✅ Recommends The One Probe Community Edition
Baubles	Unmaintained	✅ Recommends Bubbles
Shadowfacts' Forgelin	Unmaintained	✅ Replaced by Forgelin-Continuous

WARNING

If your modpack uses Bansoukou 4, make sure to run the instance at least once before installing cleanroom loader so its patches are applied.

Performance / Memory optimization mods

The most important optimization mods for Minecraft 1.12.2 can be summed up to the following list:

Chibi: Huge optimizations that are targeted at Minecraft 1.12.2.
VintageFix: Load time and RAM use improvements for Minecraft 1.12.2.
Universal Tweaks: A community project to consolidate various bugfixes and tweaks into a single solution for Minecraft 1.12.2.
Stellar Core: Provides extensive bug fixes, performance improvements, and additional features across a wide range of mods.
Gnetum: Improves performance by distributing HUD updates over multiple frames.
(May experience a few bugs, please report them Here.)
Fixeroo: Bundles bugfixes and XP orb optimizations.
Alfheim Lighting Engine: Lighting engine replacement for Minecraft, optimized for performance and fixing many bugs.

Note

Universal Tweaks supersedes a lot of mods which will be mostly not mentioned here. This can be observed via an in-game warning or by looking at the incompatible mods list Here.

Render optimization mods

The most prominent Render optimization mods for Minecraft 1.12.2 are:

Optifine (Consider pairing it with OptiNotFine)
Celeritas (Requires Cleanroom Loader, if used with Chibi, use Chibi 5.30+)
Nothirium (Also requires Naughthirium)

Note

Celeritas and Nothirium do decrease ram usage and footprint, while OptiFine may increase ram usage and will lengthen load times.

Stress Test Results

In a simulated heavy-base scenario, we benchmarked the aforementioned mods against each other, and therefore rank their performance according to which gpu is used:

NVIDIA GPUs → Nothirium > Optifine > Celeritas
AMD GPUs → Celeritas > Optifine > Nothirium
Intel Integrated Graphics → Nothirium > Optifine > Celeritas

Note

Performance varies depending on your hardware and drivers. Test all three mods to see which provides the best results for your system.

MCreator and AI Generated Mods

Old and new 1.12.2 mods made with MCreator are highly not recommended for use no matter what kind of mod it is. MCreator in 1.12.2 is no longer officially supported and mods created with it have significant issues that will impact your game, such as unoptimized code, hardcoded IDs, NBT data breakage, and difficulty to debug the generated code. You can use Crash assistant or MCreatorDetector if you want a quick way of finding out which mods are MCreator.

Mods that were created entirely using generated code from AI (rather than as a learning tool) are also highly not recommended, the mod's code will be highly varied in quality (often poor), it can also be either prone to crashes or downright placebos, especially if it is a performance related mod.

Note

If you're new to mod creation and want to start making a mod, we highly recommend creating the mod from scratch instead to avoid complications with learning.
You can join our discord server to receive support when starting your modding journey.

Superseded mods

Note

These mods are not necessarily incompatible with Cleanroom loader, but have been superseded by newer forks and mods or do not present any benefit, so we recommend the following actions. For forks not listed below, keep in mind that not all of them are beneficial. Some forks introduce extra bugs that were not in the original mod, some were forked mostly for a specific modpack's benefit and some were forked due to internal conflicts with the original mod's developers. Use those forks at your own discretion.

Library Mods

Mod	Reason	Recommended Action
Baubles	Outdated	✅ Use Bubbles If incompatibilities occur, report it here or revert to Baubles. Use other Baubles or Bubbles forks not listed here at your own discretion as there are many of them!
Custom Mob Spawner	Breaks mob spawns from almost every other mod. Salvaged features were merged into Mo' Creatures Extended and Universal Tweaks.	🚫 Remove Increased Spawn Caps: ✅ Use Universal Tweaks
Forgelin	Outdated	✅ Use Forgelin-Continuous
LibrarianLib	Will not work correctly with Forgelin-Continuous.	✅ Use LibrarianLib-Continuous (May break Wizardry Animations, Revert to LibrarianLib + Forgelin if present)
MixinBootstrap	Not Required with latest MixinBooter.	🚫 Remove
Mixin 0.7-0.8 Compatibility (MixinCompat)	Not Required with latest MixinBooter.	🚫 Remove
OpenModsLib	Merged into OpenBlocks Reopened, no other mods require it.	✅ Use OpenBlocks Reopened
Patchouli	Outdated	✅ Use Patchouli ROFL Edition If incompatibilities occur, revert to Patchouli.

Content Mods

Mod	Reason	Recommended Action
AcademyCraft	Abandoned	✅ Use Academycraft UES
Advanced Rocketry	Outdated	✅ Use Advanced Rocketry - Reworked
Aether II	Gets packaged with Phosphor which breaks compatibility with Alfheim Lighting Engine and Hesperus.	✅ Use Aether II: Phosphor Not Included
Aetherium Ashen Armor	Merged into Aetherworks Unofficial Extended Life.	✅ Use Aetherworks Unofficial Extended Life
Aetherworks	Outdated	✅ Use Aetherworks Unofficial Extended Life
Alchemistry	Outdated	✅ Use Alchemistry - Redox
Applied Energistics 2	Outdated	✅ Use AE2 Unofficial Extended Life
Avaritia 1.1x / Avaritia 1.1x Kedition	Avaritia 1.1x: Outdated Avaritia 1.1x Kedition: Alternate fork that mainly adds mod integration. Avaritia 1.1x Unofficial Extended Life has more content and fixes while most of the mod integration is retained.	✅ Use Avaritia 1.1x Unofficial Extended Life
Better Questing	Outdated	✅ Use Better Questing Unofficial
Better Questing - Quest Book / Better Questing Triggerer	Rewritten implementation in Better Questing Unofficial.	✅ Use Better Questing Unofficial
Better Questing - Standard Expansion	Merged into Better Questing Unofficial.	✅ Use Better Questing Unofficial
Binnie's Mods	Outdated	✅ Use Binnie's Mods Patched
BitHop	Outdated	✅ Use QBitHop
Bloodmoon	Has performance issues, the event lighting is not compatible with OptiFine without unofficial patches. Hyxcate's event lighting is compatible with OptiFine without requiring any patches and is more performant.	✅ Use Hyxcate
Classic Bars	Outdated	✅ Use Classic Bars Legacy
Crimson Revelations	Outdated	✅ Use New Crimson Revelations
Davinci's Vessels	Outdated	✅ Use Valkyrien Skies
Deadly Monsters	Outdated	✅ Use Deadly Monsters Patched
Dynamic Trees	Outdated	✅ Use Dramatic Trees
Earthworks	Outdated and marked as abandoned by CurseForge,	✅ Use Earthworks Unofficial Extended Life
Embers / Embers Rekindled	Outdated	✅ Use Embers Unofficial Extended Life If incompatibilities occur, revert to Embers Rekindled.
Engineered Golems	Merged into Congrega Mystica with bugs fixed.	✅ Use Congrega Mystica
Expanded Arcanum	Merged into Congrega Mystica with bugs fixed.	✅ Use Congrega Mystica
Mekanism	Outdated	✅ Use Mekanism-CE-Unofficial or Mekanism Community Edition
MmmMmmMmmMmm (Target Dummy)	The mod was rewritten entirely. Versions 2.0.0 and above have more issues and are generally more unstable compared to the original 1.14 version.	✅ Use MmmMmmMmmMmm 1.14
Mo' Creatures	Outdated, requires Custom Mob Spawner and has numerous gamebreaking bugs.	✅ Use Mo' Creatures Extended
Modular Machinery	Outdated	✅ Use Modular Machinery: Community Edition
MrCrayfish's Furniture Mod (Legacy)	Outdated	✅ Use MrCrayfish's Furniture Mod Rebuilt
Mutant Beasts	Outdated	✅ Use Mutant Creatures Legacy
Natura	Outdated, impacts performance.	✅ Use Natura Legacy
Nature's Aura	Outdated, impacts performance.	✅ Use Nature's Aura Simplified
Nyx / Nyx: RotN Edition / Xyn	Nyx: Outdated Nyx: RotN Edition / Xyn: Forks of Nyx with minor differences.	✅ Use Hyxcate
Oh The Biomes You'll Go / Biomes You'll Go Fixed	MCreator and has lots of bugs (unlike versions past 1.12.2). Use another biomes mod instead.	🚫 Remove
OpenBlocks	Outdated	✅ Use OpenBlocks Reopened
Pillar	Outdated	✅ Use Pillar Patched
Railcraft (Release version)	The mod is abandoned and the latest beta version has more bugfixes.	✅ Use Railcraft Beta
Random Things	Outdated	✅ Use Quantum Things
RPGLoot	Outdated	✅ Use RPGLoot Patched
Rustic Thaumaturgy	Merged into Congrega Mystica with bugs fixed.	✅ Use Congrega Mystica
Seared Ladder (Backport)	Merged into Tinkers' Antique.	✅ Use Tinkers' Antique
Soot	Outdated	✅ Use Soot Unofficial Extended Life
Soul Shards Respawn	Outdated	✅ Use Soul Shards Respawn Patched
Straw Golem	Outdated and no longer available in CurseForge.	✅ Use Straw Golem Unofficial Extended Life
Techguns	Outdated	✅ Use Techguns-CE
Thaumic Wonders / Thaumic Konders	Thaumic Wonders: Outdated Thaumic Konders: Alternate fork with minor fixes and some model changes. Formerly a reupload of a very early version of Thaumic Wonders Unofficial (New Wonderology).	✅ Use Thaumic Wonders Unofficial
Thicc Entities	Outdated, notably crashes with Aqua Acrobatics.	✅ Use Entifier
Tinkers' Arsenal	Outdated and no longer available in CurseForge.	✅ Use Tinkers' Arsenal Reloaded
Tinkers' Construct	Outdated	✅ Use Tinkers' Antique
Tough Expansion	Has a RCE exploit.	✅ Use Survival Tools
Twilight Forest	Outdated	✅ Use Twilight Forest: Deforestation Edition
Wizardry	Latest version causes incompats.	✅ Use Wizardry 0.11.1

Performance Mods

Mod	Reason	Recommended Action
!!Pigium - Performance	Not a legitimate performance mod. It was made to bait users for a YouTube video.	🚫 Remove
Better Biome Blend / Betterer Biome Blender	Better Biome Blend: Does not provide any meaningful performance improvements or fixes. Betterer Biome Blender: Fork of Better Biome Blend with minor fixes and mixins embedded. The mod's file size is greatly increased (36.77 KB → 1021.33 KB) due to the embedded mixins.	🚫 Remove
BetterFPS	Outdated and breaks core functionality.	🚫 Remove
Clumps	Outdated	✅ Use Fixeroo
Farsight	Does almost nothing except move `unloadChunk` from `ChunkProviderClient` to `tick`, caches chunk indefinitely, which might impact RAM usage.	🚫 Remove
FastFurnace	Merged and rewritten in Chibi.	✅ Use Chibi
FastWorkbench	Merged and rewritten in Universal Tweaks.	✅ Use Universal Tweaks
FermiumASM / BlahajASM	FermiumASM: Fork of NormalASM that disables fixes with Dynamic Trees and changes the MixinBooter dependency to use FermiumBooter instead. BlahajASM: Fork of FermiumASM that reverts the FermiumBooter dependency change. As well as all of them being slow to sync to upstream, it is overall not recommended to use any of the many Chibi forks.	✅ Use Chibi
FPS Boost	Provides no benefit.	🚫 Remove
GPU Tape	Provides no benefit.	🚫 Remove
Multithreaded Noise	Known to cause crashes, not recommended for use.	🚫 Remove
Neonium	Outdated Vintagium fork, see Render optimization mods.	🚫 Remove
NormalASM	Outdated fork of Chibi with no meaningful changes outside of changing the package name and mod id. This makes it incompatible with anything depending on the original mod id or class names. As well as all of them being slow to sync to upstream, it is overall not recommended to use any of the many Chibi forks.	✅ Use Chibi
Performant	Empty jar that does nothing.	🚫 Remove
Redirectionor	Provides no real performance benefit.	🚫 Remove
Relictium	Outdated Vintagium fork, see Render optimization mods.	🚫 Remove
Spark / Spark Unforged	Spark: Outdated Spark Unforged: Backport of modern Spark with half of the features removed.	✅ Use Flare
Surge	Uses deprecated methods, does not improve performance at all. Salvaged features are now in Universal Tweaks.	✅ Use Universal Tweaks

QoL Mods

Mod	Reason	Recommended Action
AppleSkin	Outdated	✅ Use LemonSkin
AttributeFix	Merged and rewritten in Universal Tweaks.	✅ Use Universal Tweaks
Bed Patch	Fix already included in Forge / Cleanroom Loader, does nothing when installed.	🚫 Remove
Better Foliage / RLFoliage	Better Foliage: Performance heavy and known to cause incompatibility issues with certain mods including VintageFix. RLFoliage: Fork of Better Foliage that removes the "Round Logs" feature to slightly improve performance, as well as other minor changes. Neither are recommended for use.	🚫 Remove
Born in a Barn	Fix already included in Forge / Cleanroom Loader, does nothing when installed.	🚫 Remove
Crafting Tweaks	Outdated	✅ Use Crafting Tweaks Unofficial
DupeFix Project	Incompatible with MixinBooter due to a hacky implementation. Universal Tweaks implements the same fixes while forks of the affected mods have already fixed the duplication bugs from their side.	✅ Use Universal Tweaks
Eigencraft Unofficial Patch / MUP	Lots of its fixes are now in Universal Tweaks while the lighting and redstone optimizations are not very compatible with other mods. Better alternatives already exist for lighting optimizations.	Fixes: ✅ Use Universal Tweaks Lighting Engine: ✅ Use Alfheim Lighting Engine or Hesperus
Fireproof Items	Future Fireproof has a better implementation and API features.	✅ Use Future Fireproof
Hot or Not	Outdated	✅ Use Hot or Not Plus
Immersive Craft	Outdated	✅ Use Immersive Craft Patched
Just Enough Characters	Outdated	✅ Use Had Enough Characters
JustEnoughIDs (JEID) / NotEnoughIDs (NEID)	Outdated	✅ Use RoughlyEnoughIDs (REID)
JustEnoughItems (JEI)	Outdated	✅ Use HadEnoughItems (HEI)
MiniEffects	Outdated	✅ Use MiniEffects-Legacy Extended Life
Mod Director	Outdated and no longer available in CurseForge.	✅ Use FileDirector
NetherPortalFix	Rewritten implementation in Universal Tweaks.	✅ Use Universal Tweaks
Paintings ++	Complicated to setup and not very user friendly. It is recommended to use JSON Paintings and Painting Selection GUI together instead for a much better experience.	✅ Use JSON Paintings and Painting Selection GUI
RandomPatches	Known to cause crashes with certain mods. Universal Tweaks has a good portion of its features.	✅ Use Universal Tweaks
RandomTweaks	Known to cause crashes with certain mods. Universal Tweaks has a good portion of its features.	✅ Use Universal Tweaks
SmoothFont	Breaks some mods.	🚫 Remove
Thaumic Fixes	Overwrites methods in one of Thaumcraft's classes to fix a single bug which will break compatibility with other mods trying to inject into the same class. Thaumcraft Fix has the same fix without overwriting.	✅ Use Thaumcraft Fix
Thaumic Meme	ThaumicTweaker already has a similar research subtitles feature bundled in with a better implementation.	✅ Use ThaumicTweaker
ThaumTweaks	Overwrites methods in some of Thaumcraft's classes which breaks compatibility with other mods trying to inject into the same classes. ThaumicTweaker has most of the same features without overwriting.	✅ Use ThaumicTweaker
Tinker's JEI	Tinkers' Antique already has full JEI support for materials. While both mods can still work together, it's overall recommended to remove it to not have duplicate features.	✅ Use Tinkers' Antique
Tips	Outdated	✅ Use AnotherTips

Should Have

A list of companion mods to further improve your experience with other mods.

Mod	Reason	Recommended Action
AtomicStryker's Battle Towers	Has a good amount of bugs.	✅ Add Battle Towers Fixes
Balkon's WeaponMod: Legacy	Lack of mod integration.	✅ Add Balkon's Expansion
HadEnoughItems (HEI)	Some mods have overlapping issues with HEI's interface.	✅ Add JEI Area Fixer
IC2 EXP	Has a good amount of bugs.	✅ Add IC2 Patcher
Industrial Foregoing	Has a good amount of bugs.	✅ Add IFPatcher
Just Enough Resources (JER)	Lack of mod integration.	✅ Add Just Enough Magiculture
Mowzie's Mobs	Optional Baubles integration.	✅ Add Mowzie's Mobs' Baubles Make sure to use the latest beta version of Mowzie's Mobs or it will crash!
Patchouli ROFL Edition	Optional mod integration and quality of life.	✅ Add Patchouli Books
Railcraft	Has a good amount of bugs.	✅ Add Railway Depot Worker
Thaumcraft 6	Bugs and lack of mod integration.	✅ Add Thaumcraft Fix and ThaumicTweaker (Add Congrega Mystica for more integration)
VoxelMap	Has a good amount of bugs.	✅ Add VoxelMap Fixes
Witchery: Resurrected	Base mod is not usable.	✅ Add Witchery: Companion

Cleanroom Exclusive Mods

These mod replacements and companion mods are exclusive to Cleanroom because they rely on features from it or from modern Java versions, therefore THEY WILL NOT WORK ON FORGE.

Mod	Reason	Recommended Action
Blockcraftery	Outdated and has several bugs.	✅ Use Blockcraftery: Refurbished
CodeChicken Lib	Outdated and has several bugs.	✅ Use CodeChicken Lib CRE
Charset	Outdated and has several bugs.	✅ Use Charset CRE
Emojicord	Outdated and has several bugs.	✅ Use Goslingcord If you still want to use Forge, use version 2.0.0.
GeckoLib 3	Outdated and has several bugs. SauriaLib remains compatible with existing mods that depend on GeckoLib 3.	✅ Use SauriaLib
RandomPortals	Does not work with Cleanroom Launcher and depends on RandomPatches.	✅ Use Clean Portals
Sound Filters / Sound Filters Continued	Outdated	✅ Use 籁/Sound Physics Remixin If you still want to use Forge, use version 1.1.15 or below.