EndlessIDs can open and upgrade worlds created with NotEnoughIDs without any problems (both the original and the Unofficial version). If you notice any problems when opening NEID worlds with EndlessIDs, please open an issue!

Comparison of the known limits

	Vanilla	NotEnoughIDs	NEID Unofficial	EndlessIDs
Block IDs	4,096	32,000	65,536	16,777,216
Block Metadata	16	16	65,536	65,536
Item IDs	32,000	32,000	65,536	16,777,216
Biome IDs	256	256	256	65,536
Entity IDs	256	256	256	32,768
Potion IDs	32	32	32	65,536
Enchantment IDs	256	256	256	32,768
DataWatcher IDs	32	127 (Broken)	127	65,536
Dimension IDs	Theoretically unlimited, 4,294,967,295 in practice	Same	Same	Same

Mod compat

This mod also contains patches for the following mods:

Mod list

AbyssalCraft
Advanced Rocketry
Alternate Terrain Generation
Antique Atlas
Anti ID Conflict
ArchaicFix
Atum
Biomes O' Plenty
Biome Wand
BuildCraft
ChromatiCraft
Climate Control
Compact Machines
CoFH Lib
Dark World
Dimensional Doors
DragonAPI
Dynamic Surroundings
Enderlicious
Enhanced Biomes
Erebus
Extra Planets
Extra Utilities
Futurepack
GalactiCraft
Highlands
Immersive Cavegen
Industrial Revolution by Redstone Rebooted
Matter Overdrive
More Fun Quicksand Mod
Nature's Compass
Netherlicious
Nomadic Tents
Nostalgic World Generation
Old World Gen
Random Things
Restructured
Realistic Terrain Generation
Realistic World Generation
Thaumcraft
The Lord of the Rings Mod: Legacy
ThutCore/ThutMods
Tropicraft
Twilight Forest
Underground Biomes Constructs
Witchery
WorldEdit

Mods not listed here may or may not work.

For item/block IDs:
- A good rule of thumb is that the more invasive a mod is, the higher the chance it's broken without a patch once the IDs exceed 4096 and 32000.
For biome IDs:
- If a mod adds a custom world generator, it has a high chance of invoking an old vanilla method in the worldgen code.
  
  To avoid world corruption and broken biomes, this method has been replaced with an instant crash that refers the user to this GitHub repo.

If you find any crashes or incompatibilities, don't hesitate to open an issue.

Depending On Metadata Increase In Another Mod

NOTE: This API is available as of version TODO of EndlessIDs.

EndlessIDs implements the common ID Extender API introduced in NotEnoughIDs Unofficial. See: https://github.com/GTNewHorizons/NotEnoughIds/pull/17

The description below is an excerpt of NEID-U's readme concerning this API:

In order to use the metadata, you should not create a hard dependency on the endlessids Mod ID, but rather on the idextender Mod ID. EndlessIDs bundles this "dummy" mod alongside itself.

Here is an example of how to use it, you could put this code in your Mod's pre-init for example:

import idextender;

int maxMeta = 15;

if (Loader.isModLoaded("idextender")) {
    maxMeta = (Integer) Class.forName("idextender.Metadata").getDeclaredMethod("maximumMetadata").invoke(null);
}

You can also query for the number of bits the metadata value is extended to, rather than the maximum value:

import idextender;

int metadataBits = 4;

if (Loader.isModLoaded("idextender")){
    metadataBits = (Integer) Class.forName("idextender.Metadata").getDeclaredMethod("metadataBits").invoke(null);
}

The idextender.DataWatcher class also exposes the extended DataWatcher count (used for entity data syncing over network) in a similar fashion.

Note that these values CAN be identical to the vanilla values if the ID Extension mod implementing it has a config to toggle itself, existence of the IDExtender class does not guarantee a fixed increase, and you should check that the returned value is large enough for your needs.

If for some reason, you need to know what parent mod is providing the idextender mod, you can do the following, which will give you back the Mod ID of the actual mod that has provided idextender. For example, endlessids:

// This will give back the value "endlessids" which is EndlessIDs' Mod ID
String parentIDExtender = (String) Class.forName("idextender.IDExtender").getDeclaredMethod("parentModId").invoke(null);

For more information, see the NotEnoughIDs readme.