Optional Mod Compatibility

Optional external mod compatibility

Flan's Mod Ultimate includes the following integrations on Forge 1.20.1 and NeoForge 1.21.1. Install external mods separately, using files for your Minecraft version and loader. The table describes explicit compatibility code in these branches; it does not certify every external mod release, shader pack or combination of mods.

External mod	Forge 1.20.1	NeoForge 1.21.1	Compatibility feature	Project links
Embeddium	Yes	Yes	Sends Flan model vertices through the renderer's bulk vertex API when supported, falling back to ordinary vertex submission when necessary.	CurseForge, source
Sodium	—	Yes	Uses Sodium's bulk vertex API for Flan models.	CurseForge, source
Oculus	Yes	—	Detects active shader packs and shadow passes so Flan rendering uses compatible paths.	CurseForge, source
Iris Shaders	—	Yes	Detects active shader packs and shadow passes, with compatible vertex submission and rendering fallbacks.	CurseForge, source
Entity Culling	Yes	Yes	Automatically exempts relevant Flan entities from tick culling to keep movement, sounds and effects updating; bullets and aircraft are also exempt from visibility culling.	CurseForge, source
Distant Horizons	Yes	Yes	Adds approximate far-terrain rangefinding, distant driveable contact shapes and distant explosion cues. Requires DH API 5.1 or newer; see requirements and server limits.	CurseForge, source
BuildCraft Community Edition	Fluid support	Fluid support	Generic fluid-container refuelling includes default registry patterns for BuildCraft oil and fuel families.	CurseForge, source
Just Enough Items (JEI)	Yes; 15.20+	Yes	Shows vehicle assembly and gun-box purchase requirements, engines and crafting stations; custom crafting screen titles open the corresponding JEI category.	CurseForge, source

Assessed as compatible without integration

These mods have no dedicated integration code in Flan's Mod Ultimate, but the project has assessed them as safe to run together on the listed branches.

External mod	Forge 1.20.1	NeoForge 1.21.1	Notes	Project links
ServerCore	Yes	Yes	Default settings need no changes. If you turn on activation range, exclude Flan's entities (see below).	CurseForge, source
ImmediatelyFast	Yes	Yes	No direct interaction with Flan's rendering found.	CurseForge, source
Radium Reforged	Yes	—	Forge port of Lithium. No direct interaction found.	CurseForge
Lithium	—	Yes	No direct interaction found.	CurseForge, source
More Culling Reforged	Yes	—	Forge port of More Culling. No direct interaction found.	CurseForge
More Culling	—	Yes	No direct interaction found.	CurseForge, source
ModernFix	Yes	Yes	No direct interaction found.	CurseForge, source
FerriteCore	Yes	Yes	No direct interaction found.	CurseForge, source
Redirected	Yes	Yes	No direct interaction found.	CurseForge

ServerCore activation range

ServerCore's activation range is off by default. When it is on, entities far from every player only tick occasionally, so bullets and grenades can stall in flight, and unattended driveables, AA guns and AI mechas can stutter or stop. To avoid this, add Flan's entity types to excluded-entity-types in config/servercore/optimizations.yml:

excluded-entity-types:
  - flansmodultimate:bullet
  - flansmodultimate:grenade
  - flansmodultimate:thrown_gun
  - flansmodultimate:deployed_gun
  - flansmodultimate:aa_gun
  - flansmodultimate:plane
  - flansmodultimate:vehicle
  - flansmodultimate:mecha
  - flansmodultimate:driveable_seat
  - flansmodultimate:driveable_wheel
  - flansmodultimate:flybyplane
  - flansmodultimate:aimecha

Keep ServerCore's own default entries in the list as well. If you use the Custom NPCs module, consider excluding customnpcs:customnpc too. Dynamic view distance may shorten how far players see distant vehicles and aircraft while the server is under load.

Rendering and installation

Embeddium and Sodium are alternative renderers. The entries above indicate which APIs Flan's Mod can use on each branch; follow the renderer and shader mod's own dependency requirements when choosing a combination. Rendering integrations and Entity Culling run on the client. Distant Horizons is also optional on the client; servers do not need DH installed for Flan's integration.

With an active Oculus or Iris shader pack, Flan's experimental GPU model cache falls back to the standard rendering path. Installing the shader mod with shaders disabled leaves the cache available. Forge 1.20.1 also detects OptiFine and disables the GPU cache as a compatibility fallback; this is more limited than the Oculus/Iris API integration. See Rendering Performance.

Fluid fuels

BuildCraft compatibility uses the loader's fluid-container support rather than a BuildCraft API dependency. Put a supported fuel container in a driveable's fuel or cargo inventory. The common fluidFuels defaults are buildcraftenergy:oil*; 1000 and buildcraftenergy:fuel*; 2000, measured in Flan fuel units per bucket. Matching registry IDs and exposed fluid containers are what matter; other mods' fluids can be configured too. This does not imply support for every BuildCraft machine or direct pipe connection to a driveable.

See Mod Config for fluid fuel configuration.

Custom NPCs and companion modules

Custom NPCs is optional for the main mod, but required by the separately installed Flan's Ultimate 2: Wolff's NPC Vehicles & Soldiers module. That module adds Flan models for NPCs, soldiers and vehicle crews/drivers. Use the Custom NPCs build required by the module for your Minecraft version. See NPC Vehicles and Soldiers for setup. The project's own Packs Manager and content packs are separate project artifacts, rather than external compatibility mods.