Overview
LOTR LimitlessIDs is the essential engine expansion coremod for Minecraft 1.7.10 and The Lord of the Rings Mod (v36.15). By upgrading internal ID tables from 12-bit / 16-bit to 24-bit, it expands the block and item ID ceiling to 16,777,216. Built specifically to eliminate ID exhaustion crashes in large modpacks while preserving the LOTR Mod's intricate biome variant metadata and world save integrity, it is a foundational engine mod for any modern 1.7.10 setup.
At a glance
| Status | Released |
| Version | v1.2.0 |
| Updated | 31 Aug 2026 · 2 months ago |
| Downloads | 111 on CurseForge |
| Type | Mod |
| Minecraft | 1.7.10 · Forge |
| LOTR Mod | v36.15 |
| Requires | Forge 10.13.4.1614 or later |
| Install on | Client and server |
| File size | 208 KB |
| Tags | coremodidscompatibilityperformance |
| Also known as | LOTR LimitlessIDsLimitlessIDsLOTRLimitlessIDs1.7.10 Limitless IDsLimitless IDs ModMinecraft 1.7.10 ID limit fixlotr limitlessids |
What's new
v1.2.0, out 31 Aug 2026.
Changelog
Notable changes to LOTR LimitlessIDs below:
1.2.0
- Biomes O' Plenty expansion: Patched BOPBiomeManager.getNextFreeBiomeId to expand search bounds from 256 to 65536 via BiomeHooks.biomeListSize(). Prevents unhandled IllegalArgumentException when the initial 256 biome slots are filled in heavy modpacks.
1.1.9
- AntiIdConflict neutralization: Patched BiomesManager and PotionsManager in AntiIdConflict to neutralize artificial crash exceptions on overlapping IDs.
- Validated compatibility across 264 mod JARs from a user's WOTR custom modpack.
1.1.8
- Erebus biome initialization: Patched erebus.ModBiomes to bypass hardcoded exception checks on pre-allocated biome IDs, allowing IdArbiter to relocate Erebus biomes to free slots in the 65k registry.
- Early LOTR range reservation: Eagerly verified LOTR profile in static initialization so foreign biomes requesting IDs 0..170 are automatically shifted to candidate IDs above 170.
1.1.7
- Non-final registry arrays: Stripped ACC_FINAL modifiers on Potion.potionTypes (field_76425_a), Enchantment.enchantmentsList (field_77331_b), and BiomeGenBase.biomeList (field_76773_a).
- Fixed IllegalAccessException on reflection-based potion resizers (such as Immersive Engineering IEPotions.extendPotionArray).
1.1.6
- EntityRegistry expansion: Widened available indices from 256 to 65536 and routed findGlobalUniqueEntityId() to EntityRegistryHooks, resolving the "No more entity indicies left" crash during mob registration.
- JVM method size protection: Removed caller-side GameRegistry bytecode injection loop that pushed large item registration methods (such as History Items HIRegistry) over the 64 KB JVM limit.
1.1.5
- BlockFire flammability: Added dynamic array resizing in BlockFireHook for block IDs above 4095.
- Fixed VerifyError in BlockFire.setFireInfo by providing dedicated hooks for integer ID and Block object overloads.
1.1.0
- Initial WOTR heavy modpack support up to version alpha-3k.
- CubicChunks support: Handled 32-bit Y coordinates in S23PacketBlockChange and added runtime CubicChunks detection.
- Screen recovery: Added Tessellator state recovery on "Already tesselating!" errors during GUI screen switches.
- Packet stream symmetry: Fixed 1-byte desync in S23PacketBlockChange.readPacketData.
1.0.0
- Initial release of LOTR LimitlessIDs.
- 24-bit block IDs (16.7M) with dynamic compaction.
- 32-bit item IDs (idExt).
- 16-bit biomes (65536) and DFU format migration.
- 16-bit potions (65536) and 15-bit enchantments (32768).
- 16-bit global entity IDs (65536).
- 4096 LOTR biome variant support via LOTRBiomeVariantsS.
From the release notes on CurseForge · this file on CurseForge
What it does
- Up to 16,777,216 block IDs and 16,777,216 item IDs
- Up to 65,536 biomes (older Biomes16 and Biomes16v2 worlds still load), 32,768 enchantments, 65,536 potions and 65,536 entity IDs
- A separate table with 4,096 slots for LOTR biome variants, so Middle-earth's sub-biomes and Utumno keep working
- When two mods want the same ID, it hands one out from a saved list, and never touches vanilla or LOTR slots
- Each world keeps its IDs in lotrlids-world-ids.properties, so blocks and items don't get scrambled after a restart or a mod update
- Works with OptiFine shaders, FastCraft, Angelica and lwjgl3ify
- In-game commands: /lotrlids info, palette, doctor, benchmark and export
Install
- Drop the jar into mods/ with the LOTR Mod v36.15 and Forge 10.13.4.1614 or newer.
- Run /lotrlids doctor after the first launch. It checks its own hooks and tells you if another ID extender is fighting it.
- CubicChunks isn't fully supported.
First time setting up LOTR Mod addons? The install guide covers Forge, the LOTR Mod, and what goes on a server.
Reporting
Open an issue with screenshots, the exact jar version and the part of the log where it breaks. Not sure it's a bug? Ask on Discord first.
Credits
Made for The Lord of the Rings Mod by Mevans. Not affiliated with it.
Frequently asked questions
Common questions about LOTR LimitlessIDs, compatibility, and gameplay.
How many IDs does LOTR LimitlessIDs provide?
It raises Minecraft 1.7.10's restrictive 4,096 block limit and 32,768 item limit up to 16.7 million IDs (24-bit space), eliminating registry exhaustion crashes when installing large modpacks.
Will LOTR LimitlessIDs corrupt existing world saves?
No. Unlike legacy ID extenders, LOTR LimitlessIDs includes a world format protection layer specifically designed to protect existing 1.7.10 world saves, keeping submod blocks and LOTR biome data safe.
Is LimitlessIDs compatible with OptiFine, FastCraft, and other coremods?
Yes, LOTR LimitlessIDs runs smoothly alongside OptiFine, FastCraft, Angelica, NEI, and major 1.7.10 coremods.
Can I install LOTR LimitlessIDs on dedicated servers?
Yes, it must be installed on both the server and client in multiplayer environments to synchronize the extended ID space.
