Source-provided project description. FreeMinecraftMods keeps creator credit and adds separate compatibility and decision guidance below.

Project overview

Cerulean is a mod that optimizes Minecraft's advancement checking system, specifically the laggy InventoryChangeTrigger, which can cause heavy lag in modpacks with lots of modded advancements. It is a fork of Icterine , updated to modern versions and with additional features. Aside from being updated to 1.21.1, Cerulean adds an option to only process advancements every few ticks, which is the strategy used by mods like Achievements Optimizer (which does not work with the original Icterine). This option is handled in a way that ensures the first time an item is picked up per player, it is always processed for achievements--preventing cases where advancements would stall until you moved items around. From the original mod page : Optimizes triggering advancements for obtaining items; Might break parity with vanilla, but doesn't affect vanilla advancements and shouldn't affect the vast majority of mods/datapacks; Even if it does affect something, advancement still should be obtainable by just dropping and picking up one of required items; Currently, there are no known incompatibilities or issues; Every injection into vanilla code can be disabled in config file. All changes are server-side.

FreeMinecraftMods decision guide

This mod is most relevant to players looking for Performance on Fabric, NeoForge, Forge. Treat those labels as discovery hints, then verify the exact file and dependency list on the official project page.

The latest stored update signal is May 3, 2025. Older projects can still work well, but they deserve extra compatibility testing before being added to a current world or public server.

What to verify before choosing a file

Confirm that the file is published by the credited creator on the linked official source.
Match the Minecraft version exactly instead of relying only on a broad category label.
Read dependencies, incompatibilities, and changelog notes before updating an existing instance.
Match the loader or server platform and its required version. Forge and NeoForge are not interchangeable.
Back up worlds and configuration files before testing the project in a long-term save or public server.

Compatibility at a glance

Minecraft versions in this snapshot: 1.21.1, 1.20.1, 1.20

Loaders and platforms: Fabric, NeoForge, Forge

Performance

Before you install

Match the exact Minecraft version and loader, install every required dependency, and test in a separate profile before opening an important world. Keep a backup before changing a working mod list.

Source, licensing, and corrections

FreeMinecraftMods does not mirror the project files. Use the official source for downloads, release notes, dependencies, support, and licensing details. Project names, images, and creator-written descriptions remain the property of their respective owners.

How listings are reviewed | Report incorrect project information | Rights-holder and DMCA information

Limited catalog information

This source record is available for discovery, but it does not yet contain enough verified description, classification, image, freshness, or compatibility information to be indexed as a full editorial page. It is therefore marked noindex and is not eligible for advertising.

Cerulean