Check out meldexun's fork for more features

Tweaker to handle miscellaneous issues in Minecraft 1.12.2 modpacks.

RLTweaker focuses primarily on bug fixes and performance improvements, but also has plenty of quality of life features and toggles that you may find useful for your modpack.

The mod is developed primarily for RLCraft but it is 100% okay to use in any other modpack.

This mod works server side only! (More features are available if the client has the mod)

You don't have to configure anything, you can just drop the mod into the modpack and it will start working, only improvements are enabled by default.

It is recommended to run the command /rladvisor after starting up your modpack, though, as it will give you some advice on which patches to enable or disable.

List of tweaks:

Minecraft
(Patch) aggressiveMotionChecker: Aggressively tackles motion issues with dividing by zero
(Patch) chunkTicks: Enables features for ticking chunk blocks
(Patch) doorPathfindingFix: Fixes mob pathfinding to let them travel through doors
(Patch) lessCollisions: Improves collision performance in modpacks that have an increased max entity radius. Can be configured in JSON
(Patch) particleThreading: Makes particles thread safe to prevent particle corruption
(Patch) patchAnvilDupe: Patches numerous anvil dupes caused by mods
(Patch) patchBroadcastSounds: Enables config option to tweak broadcasted sounds
(Patch) patchEnchantments: Enables config option to enable blacklisted enchantments
(Patch) patchEntityBlockDestroy: Enables config option to blacklist entities destroying blocks
(Patch) patchHopper: Enables some config options for tweaking hoppers
(Patch) patchItemFrameDupe: Fixes a dupe with modded item frames
(Patch) patchOverlayMessage: Allows the client to tweak overlay messages
(Patch) patchPushReaction: Enables blacklisting entities from being pushed by pistons
(Patch) pathfindingChunkCacheFix: Stops ghost chunkloading when creating pathfinding chunk caches
(Patch) reducedSearchSize: Slight optimization with mods that search for items or players and have an increased max entity radius
(Patch) serverCompatibility: Adds patches to attempt to be compatible with alternative server software
(Client) Overlay Text Drop Shadow: [Requires patchOverlayMessage] Adds a dropshadow to overlay text
(Client) Overlay Text Offset: [Requires patchOverlayMessage] Shifts overlay text up or down
All Zombies Break Doors: Allows all zombies to break doors
Blacksmith Chest Tweak: Removes some trades from blacksmith chests to match Tough as Nails functionality
Broadcasted Sounds Distance Limit: [Requires patchBroadcastSounds] Distance in blocks to send broadcasted sounds
Cleanup Mineshaft Worldgen Files: Wipes mineshaft dat regularly to save RAM
Container Distance Classes: Closes specified container classes when far away to prevent dupes
Damage Tilt Effect: Restores Minecraft 1.2.5 Damage Tilt effect
Enchantment Blacklist: [Requires patchEnchantments] Prevents enchantments from showing up naturally
Entity Block Destroy Blacklist: [Requires patchEntityBlockDestroy] Prevents entites from destroying blocks (may not work with some entities)
Entity Push Prevention: [Requires patchPushReaction] Blacklist to prevent pistons pushing entities
Hopper Block Blacklist: [Requires patchHopper] Prevents hoppers from interacting with specified blocks
Less Collisions: [Requires lessCollisions] Enables the patch functionality, toggle the patch instead
Lightning Destroys Items: Whether lightning destroys items
Lightning Sound Chunk Distance: How far away in chunks lightning can be heard
Motion Checker: Attempt to prevent entities from moving too fast or incorrectly
Motion Checker Speed Cap: Maximum speed entities can move, if motion checker is enabled
Player Arrow Sync: Sync the motion and position of arrows with the client
Player Dismount Sync: Sync a player's mount and dismounting with the client
Witch Potion Replacements: Option to replace witch potions with other potion effects
Witch Potion Replacements - Harming: Swaps out harming potion with a random potion in the list
Witch Potion Replacements - Poison: Swaps out poison potion with a random potion in the list
Witch Potion Replacements - Slowness: Swaps out slowness potion with a random potion in the list
Witch Potion Replacements - Weakness: Swaps out weakness potion with a random potion in the list

Aquaculture
Fix Freshwater Bug: Fix bug where modded biomes become freshwater
Fix Neptunes Bounty Loot: Fix bug where neptunes bounty never gives ingots

Battle Towers
Change Tower Explosion owner: Makes tower explosions not belong to the tower conqueror
Consistent Tower Generation: Makes tower generation based on world seed
Dimension Blacklist: Blacklists towers from generating in certain dimensions
Dimension Blacklist Enabled: Enables the aforementioned dimension blacklist
Dimension Blacklist is Whitelist: Whether the dimension blacklist is a whitelist
Enforce Tower Destruction Config: Prevents clients from changing the tower destruction config
Golem Anvil Fix: Prevents golems taking damage from anvils
Golem Auto Dismount: Golems attempt to dismount from mounts like boats or minecarts
Golem Dormant Speed Fix: Prevent dormant golems from building up speed
Golem Drowning Fix: Prevent golems from drowning
Golem Falling Block Fix: Prevent golems from taking damage by falling blocks
Golem High Aggression: Makes golems more persistent
Golem Lycanites Fluid Fix: Prevent golems from taking damage from Lycanites Mobs fluids
Golem Lycanites Projectile: Wher to swap the golem projectile with a Lycanites Mobs projectile
Golem Lycanites Projectile Name: The name of the projectile to swap with
Golem Lycanites Projectile Scale Modifier: Scale of the projectile
Golem Lycanites Projectile Speed Modifier: Speed of the projectile
Golem Speed Cap: Max horizontal speed of the golem
Golem Speed Cap Upwards: Max upwards speed of the golem
Golem Suffocating Fix: Prevent golems from suffocating in blocks
Remove Unloaded Tower Destroyers: Removes tower destroyers from unloaded worlds

Baubles
Miner's Ring Dupe Fix: Fix dupe with miner's ring

Better Combat
(Patch) betterCombatCriticalsFix: Adds critical hit events to BetterCombat
(Patch) betterCombatMountFix: Fixes mounted combat

Better Survival
Mob Blindness: Whether blindness affects mob's pathfinding
Mob Blindness Blacklist: Blacklisted mobs for the blindness effect
Mob Blindness Percentage: How strongly blindness affects mob pathfinding
Range Speed Multiplier: Multiplier for Range enchantment's speed boost
Replace Combo Handler: Replaces the blindness and combo handler entirely for performance
Replace Enchantment Handler: Replaces the enchantment handler entirely for performance
Tunneling Blacklist: Block blacklist for the Tunneling enchantment
Tunneling Blacklist Enabled: Whether the aforementioned blacklist is enabled
Tunneling Blacklist is Whitelist: Whether the blacklist is a whitelist
Tunneling Breaks Tile Entities: Whether tunneling breaks tile entities
Tunneling Cancelable: Whether tunneling should stop if the center block breaking event is canceled

Carry On
Quark Chest Fix: Prevent quark chests from being placed next to each other
Tile Entity Drop Safety Check: Prevent glitched tile entities from being created

Charm
Disable Magnetic Enchantment: Option to disable the effect of Magnetic without unregistering it to avoid packet issues. Use this if the enchantment is broken.
Fix Charged Emerald Crash: Fix charged emeralds crashing when being fired from a dispenser. (thanks Rainy Afternoon)
Fix Incorrect Item Enchantments: Fix for some enchantments being applied to incompatible items
Fix Salvage Trade: Fix for salvage trade being added to villagers when disabled

Classy Hats
(Client) Fix Bag Screen: Fixes bag screen so it actually works
(Client) Mo Bends Compatibility: Adds hat compatibility to Mo' Bends
Hat Dupe Fix: Fixes dupe with hats

Dynamic Surroundings
Environment Service Delay: Delay the environment service for village detection so it runs every second instead of every tick

Fancy Block Particles
(Client) Fix Placement Ghost Blocks: Prevents ghost blocks from being placed where placement is restricted

Googly Eyes
(Client) Entity Blacklist: Alternative entity blacklist that uses entity registry names

Grappling Hook Mod
(Outdated) Grappling Hook Fall Damage: Adds fall damage to grappling hook mod
(Outdated) Hinder Grappling While Falling: Makes it harder to aim downwards while falling

Ice and Fire
(Patch) fixOldGorgon: Fixes Ice and Fire 1.7.1 Gorgon to not cause player invincibility
(Patch) fixOldHippocampus: Fixes Ice and Fire 1.7.1 Hippocampus inventory
(Patch) IafFixMyrmexQueenHiveSpam: Fixes Ice and Fire myrmex queen spamming hives when in the sky
Deathworm Eggs Ignore Looting: Option to have death worms ignore looting enchantments
Myrmex Queen Trade Fix: Fix for myrmex queens having the wrong resin type trades
Right Hand Dragon Interaction: Fix for interacting with dragons with the offhand
Statue Data Fixes: Removes data from statues to fix some bugs
Statue Mob Griefing Fix: Prevents statues from griefing
Stop Gorgon Targeting Player Statues: Prevents gorgons from whacking player statues (they still stare)

Infernal Mobs
Use Enchantment Blacklist: Whether infernal mobs shouldn't drop items with blacklisted enchantments in the rltweaker minecraft config section

Level Up Reloaded
Pets Use Skills: Whether pets should be allowed to use skills
Stealth Overhaul: Overhauls the stealth system
Stealth Overhaul Base Distance: How far by default mobs can see you while sneaking (if stealth is above zero)
Stealth Overhaul Distance Per Level: How much closer you can be to a mob every sneak level
Stealth Overhaul Lycanites: Whether stealth should work on Lycanites Mobs (not bosses)

Lost Cities
GenerationCacheCleanupEnabled: Experimental, cleans up the generation cache to stop memory leaks
GenerationCacheMaxCount: How many entries the cache must have before being cleaned up

Lycanites Mobs
(Patch) lycanitesPetDupeFix: Fixes a dupe in earlier Lycanites Mobs versions than 2.0.8.0
Enable Entity Data Lycanites Mobs: Adds ForgeData tags (boolean) rltweaker.lycanitesboss and (int) rltweaker.lycanitesbossrange to make any entity a boss

Mantle
(Client) Remove Mantle Health Bar: Removes mantle health bar override

Quark
Ancient Tomes Alternate Behavior: Removes anvil recipe, requires tome to be in offhand to merge with the item in mainhand for free.

Potion Core
(Client) Magic Shielding HUD Fix: Fix for magic shielding affecting other UI elements
(Client) Overloaded Armor Bar Compatibility: Adds compatibility with Overloaded Armor Bar
(Client) Render Armor Icons: Whether to render armor icons
(Client) Render Armor Resistance: Whether to render armor resistance

RealBench
(Patch) realBenchDupeBugFix: Fixes dupe with RealBench

Recurrent Complex
Clean Structure Data: Removes structure data to save RAM, highly recommended
Clean Structure Data Threshold: How many data entries must exist before cleaning up
Generate Structures Partially: Whether to generate and reload structures one chunk at a time
Manage Recurrent Complex Events: Whether any of these features work at all

Reskillable
(Client) Toggleable Traits: Asks the server to toggle traits when clicking on them
Custom Transmutation: Allows JSON configuration for transmutation
Toggleable Traits: Allow players to toggle traits by clicking on them

Roguelike Dungeons
Prevent Fatigue Crash: Prevents crash with Mining Fatigue

Ruins
Chunk Logger Cleanup: Reduces RAM usage by cleaning up the chunk logger
Chunk Logger Threshold: How many chunks must be logged before cleanup is run
Remove RUINSTRIGGER Functionality: Removes the command block RUINSTRIGGER feature, as nothing used it and it causes issues with player chunkloading

Scape and Run: Parasites
Parasites Biomass Crash Fix: Fix for biomass crash
Parasites Dimension Blacklist: Forcefully removes parasites from dimensions
Parasites Dimension Blacklist Enabled: Whether the aforementioned blacklist is enabled
Parasites Sleep Prevention: Whether parasites should be able to prevent sleep

Serene Seasons
Replace Random Update Handler: [Requires chunkTicks] Replaces the random update handler with a faster alternative for performance.

So Many Enchantments
These fixes are all present in So Many Enchantments 0.5.x
Update So Many Enchantments to 0.5.x and use the config in that mod instead.

Spawner Control
Remove World Ticks: Removes world ticks, which are used to create smoke particles and remove obsolete spawners, to save performance.
Synchronize Spawner Iteration: Attempt to fix crash with mob spawners

Tough as Nails
Fix Dismount Thirst Drain Bug: Fix thirst permanently draining after dismounting
Fix Extra Attack Bug: Remove the extra attack caused by the mod
Send Extra Thirst Packets: Send more thirst packets to prevent desyncs
Teleport Thirst Fix: Fix thirst being drained when teleporting
Teleport Thirst Threshold: How exhausted you must get in a tick before the teleport fix kicks in
Thirst Packet Frequency: How frequently in ticks extra thirst packets should be sent

Waystones
(Patch) fixWaystoneScrolls: Fixes crash for bound and return scrolls. Also stops them from setting spawn.
Remove Waystone Biome Name: Removes the biome name from waystones in villages

Server Specific Patches and Tweaks
(most of these require the serverCompatibility patch)

CatServer
Charm beacon fix
Disenchanter crash fix
LootTweaker fix
Realbench patch fix

Mohist
Charm beacon fix
LibrarianLib crash fix
LootTweaker fix
Realbench patch fix

Sponge
LootTweaker fix
Pathfinding Chunk Cache patch is skipped if sponge is detected (serverCompatibility setting ignored)

All tweaks can be disabled via the config in-game (most require a game restart)