Dimension Separator: Full Control Over What Spawns Where in Minecraft
Ever tried to build a lore-friendly server where magic simply does not exist in the overworld, only to watch a wizard tower sprout up next to spawn? That exact frustration is what led to the creation of Dimension Separator, a Forge mod that gives pack makers and server admins surgical control over which modded content is allowed to appear in each dimension. Instead of fighting with datapacks or manually disabling entire mods, you decide, per dimension, exactly what gets through.
What Dimension Separator Actually Does
At its core, the mod acts as a gatekeeper. For every dimension you configure, you can either blacklist mod namespaces you want gone or whitelist only the ones you want to keep. Once a namespace is blocked, the mod can prevent several categories of content from that mod appearing in that dimension:
- World generation features such as ores, plants and structures
- Mob spawning from blocked mods
- Loot tables, including chest loot and mob drops
- Item usage when right-clicking blocks, air or entities
- Structure generation tied to the blocked namespace
Each of these categories can be toggled independently, so you could, for example, allow a mod's decorative blocks to generate while still blocking its hostile mobs from spawning. That granularity is what makes Dimension Separator for Minecraft genuinely useful for themed servers, modpacks with strict progression, and anyone building a custom dimension with its own rules.
Supported Versions and Loader
The mod is built for Forge and has been tested on Minecraft 1.20.1 with Forge 47.1.3 and above. It relies on Mixins and event handlers, which means it should play nicely with the vast majority of Forge mods. If you do hit a conflict, the developer welcomes bug reports, so compatibility issues tend to get addressed rather than ignored.
How to Install Dimension Separator
If you already run a Forge profile, setup is straightforward. Here is the short version of how to install it:
- Install a matching Forge version for Minecraft 1.20.1 (47.1.3 or newer).
- Place the mod jar file into your mods folder.
- Launch the game once so the config file generates.
- Open config/dimensionseparator.json and edit it to match your pack's needs.
- Restart the game or server to apply your changes.
If you would rather skip manual file juggling, the foxygame.net launcher handles the whole process in a single click and keeps Dimension Separator updated automatically whenever a new build drops, so your version compatibility stays sorted without you lifting a finger.
Understanding the Config File
Everything is driven by one JSON file, which keeps things refreshingly simple. For each dimension you list, you define a few key fields:
- mode — set to "blacklist" to block the listed mods, or "whitelist" to allow only them.
- bypassLevel — the minimum operator permission level allowed to summon blocked entities. Set it to -1 or omit it to disable bypass entirely.
- namespaces — the mod IDs you want to block or allow, depending on your mode.
- blacklistedIds — specific entries that are always blocked, regardless of mode, such as a single mob.
- whitelistedIds — specific entries that are always allowed, even if their namespace is otherwise blocked.
- features, mobs, loot, items, structures — booleans that switch blocking on or off for each category.
A handy detail: setting any category to false disables blocking for that category entirely, even if the namespace appears in your list. That makes it easy to fine-tune behavior without rewriting your whole config.
A Quick Example
Imagine you want a vanilla-flavored overworld with no magic mods and no zombies. You would set the overworld to blacklist mode, list the offending namespaces, and add the zombie entity to blacklistedIds. Meanwhile, your custom dimension could use whitelist mode to allow only the content you designed it around. This is exactly the scenario the mod was built for, and it works without touching the mods themselves.
Known Limitations Worth Knowing
No mod is perfect, and it helps to understand the edges of this one. Running /locate on a blocked structure will search forever without a result, since that is standard vanilla behavior when no matching structure exists. Client-side keybinds are also not intercepted, meaning a player could still open a mod's GUI with a custom key. Since they cannot interact with the blocked content anyway, this is largely harmless in practice.
Final Thoughts
Dimension Separator fills a gap that many pack authors have felt for years: real, per-dimension control without gutting your mod list. Whether you are running a lore-heavy roleplay server or building a progression pack where certain content only belongs in certain realms, this mod hands you the levers. Configure it once, and your dimensions finally behave the way your design intended.