MobSpawnController

MobSpawnController is a lightweight Fabric / NeoForge /Forge mod that lets you control mob spawning behavior and attributes through commands or an intuitive in-game GUI.

## Features
Spawn Control

- Enable or disable spawning for any mob, per spawn type (NATURAL, SPAWNER, BREEDING, EVENT, etc.)
- Fine-grained control: disable natural spawning while keeping spawner-based spawning, or vice versa
- Works with all mods' mobs — if it's registered as an entity type, it can be controlled
- Refactored spawn interception logic so rules are enforced before mobs actually spawn
Natural Spawn Rules (New in 1.1.0)

- Full InControl-style natural spawn condition system for each mob
- Configure: spawn chance, height range, total/sky/block light, time of day, world day, moon phase, player distance, world-spawn distance, local difficulty, weather, difficulty, sky visibility, fluid type, slime chunk, dimensions, biomes, biome tags, seasons, structures, blocks below/at/above, dimension player count, nearby mob cap, and more
- Blank or unset conditions are treated as unrestricted
Season Compatibility (New)

- Optional integration with Serene Seasons
- Restrict natural spawns to specific sub-seasons
- If Serene Seasons is not installed, season conditions are ignored and never block spawning
Attribute Override

- Modify any mob attribute (health, damage, speed, armor, knockback resistance, etc.) on a per-mob basis
- Supports numeric and percentage-based attribute controls
- Attribute overrides are applied when mobs finalize their spawn, and max health is resynchronized automatically
In-Game GUI

- Visual mob list with 3D entity preview
- Search by mob ID or translated name
- Filter by source mod, spawn status (enabled/disabled/partial), attribute modification status, and natural spawn configuration status
- Tabbed editor for spawn rules, natural spawn conditions, and attributes
- Structure picker, dimension/biome/block list editors, and more
- Block editor supports manual entry, held block, targeted block, and block-below quick-add
Commands

- /mobspawncontroller <mob> <spawnType> <true|false> — toggle spawn rules
- /mobspawncontroller list [mob] — view current rules
- /mobspawncontroller clear <mob|all> — reset rules
- Short alias: /msc
- Tab-completion for mob IDs and spawn types
Storage

- Rules are saved as JSON per world in data/mobspawncontroller/rules.json
- Automatically loads on server start, saves on server stop
Notes

- All features from MobSpawnSwitch have been moved here. MobSpawnSwitch is discontinued and will not receive further updates.
- The GUI requires the mod to be installed on the client. Commands and rule storage still work in a dedicated-server-only setup.

MobSpawnController is a lightweight Fabric / NeoForge /Forge mod that lets you control mob spawning behavior and attributes through commands or an intuitive in-game GUI.

Features

Spawn Control

• Enable or disable spawning for any mob, per spawn type (NATURAL, SPAWNER, BREEDING, EVENT, etc.)

• Fine-grained control: disable natural spawning while keeping spawner-based spawning, or vice versa

• Works with all mods' mobs — if it's registered as an entity type, it can be controlled

• Refactored spawn interception logic so rules are enforced before mobs actually spawn Natural Spawn Rules (New in 1.1.0)

• Full InControl-style natural spawn condition system for each mob

• Configure: spawn chance, height range, total/sky/block light, time of day, world day, moon phase, player distance, world-spawn distance, local difficulty, weather, difficulty, sky visibility, fluid type, slime chunk, dimensions, biomes, biome tags, seasons, structures, blocks below/at/above, dimension player count, nearby mob cap, and more

• Blank or unset conditions are treated as unrestricted Season Compatibility (New)

• Optional integration with Serene Seasons

• Restrict natural spawns to specific sub-seasons

• If Serene Seasons is not installed, season conditions are ignored and never block spawning Attribute Override

• Modify any mob attribute (health, damage, speed, armor, knockback resistance, etc.) on a per-mob basis

• Supports numeric and percentage-based attribute controls

• Attribute overrides are applied when mobs finalize their spawn, and max health is resynchronized automatically In-Game GUI

• Visual mob list with 3D entity preview

• Search by mob ID or translated name

• Filter by source mod, spawn status (enabled/disabled/partial), attribute modification status, and natural spawn configuration status

• Tabbed editor for spawn rules, natural spawn conditions, and attributes

• Structure picker, dimension/biome/block list editors, and more

• Block editor supports manual entry, held block, targeted block, and block-below quick-add Commands

• /mobspawncontroller <spawnType> <true|false> — toggle spawn rules

• /mobspawncontroller list [mob] — view current rules

• /mobspawncontroller clear <mob|all> — reset rules

• Short alias: /msc

• Tab-completion for mob IDs and spawn types Storage

• Rules are saved as JSON per world in data/mobspawncontroller/rules.json

• Automatically loads on server start, saves on server stop Notes

• All features from MobSpawnSwitch have been moved here. MobSpawnSwitch is discontinued and will not receive further updates.

• The GUI requires the mod to be installed on the client. Commands and rule storage still work in a dedicated-server-only setup.