Nether Structure

Nether Structure Example: Nether Devil

This walkthrough demonstrates creating a Nether-specific structure using the Nether Devil structure from MoogsVoyagerStructures. Nether structures use special placement algorithms optimized for Nether terrain.

Overview

The Nether Devil structure demonstrates:

• Nether-specific structure type
• Land search direction
• Nether biome configuration
• Land search direction options

File Structure

data/mvs/
├── structure/
│   └── other_decoration/
│       └── nether_devil.nbt
└── worldgen/
    ├── structure/
    │   └── nether_devil.json
    ├── structure_set/
    │   └── nether_devil.json
    └── template_pool/
        └── other_decoration/
            └── nether_devil/
                └── start_pool.json

Step 1: Create the NBT File

1. Build your Nether Devil structure in Minecraft
2. Design for Nether terrain (ledges, lava, open spaces)
3. Save as nether_devil.nbt
4. Place at: data/mvs/structure/other_decoration/nether_devil.nbt

Design Tips:

• Nether structures often spawn on ledges or floating platforms
• Account for lava lakes and open spaces
• Consider Nether's vertical nature

Step 2: Create the Template Pool

File: data/mvs/worldgen/template_pool/other_decoration/nether_devil/start_pool.json

{
  "name": "mvs:nether_devil/start_pool",
  "fallback": "minecraft:empty",
  "elements": [
    {
      "weight": 1,
      "element": {
        "location": "mvs:other_decoration/nether_devil",
        "processors": "minecraft:empty",
        "projection": "rigid",
        "element_type": "minecraft:single_pool_element"
      }
    }
  ]
}

Explanation

Same as overworld structures - no special requirements for Nether.

Step 3: Create the Structure JSON

File: data/mvs/worldgen/structure/nether_devil.json

{
  "type": "moogs_structures:moogs_structures_generic_nether_jigsaw_structure",
  "start_pool": "mvs:other_decoration/nether_devil/start_pool",
  "size": 1,
  "biomes": "#mvs:has_structure/nether_biomes",
  "land_search_direction": "HIGHEST_LAND",
  "cannot_spawn_in_liquid": true,
  "step": "surface_structures",
  "terrain_adaptation": "beard_thin",
  "start_height": {
    "absolute": 0
  },
  "spawn_overrides": {}
}

Key Differences from Overworld Structures

Nether Structure Type

{
  "type": "moogs_structures:moogs_structures_generic_nether_jigsaw_structure"
}

Important: Must use moogs_structures_generic_nether_jigsaw_structure for Nether structures!

Land Search Direction

{
  "land_search_direction": "HIGHEST_LAND"
}

Options:

• "HIGHEST_LAND" - Places on highest solid block (most common)
• "LOWEST_LAND" - Places on lowest solid block
• "FIXED_HEIGHT" - Skips the search and places at start_height

Why: Nether terrain is complex with many ledges and platforms. Land search finds the best placement location.

Nether Biomes

{
  "biomes": "#mvs:has_structure/nether_biomes"
}

Nether Biome Tag: data/mvs/tags/worldgen/biome/has_structure/nether_biomes.json

{
  "values": [
    "minecraft:nether_wastes",
    "minecraft:crimson_forest",
    "minecraft:warped_forest",
    "minecraft:soul_sand_valley",
    "minecraft:basalt_deltas"
  ]
}

Optional: Ledge Offset

You can add a Y offset for ledge placement:

{
  "ledge_offset_y": 5
}

Adjusts structure position by 5 blocks when placing on ledges.

Field-by-Field Explanation

• type: Nether-specific structure type
• start_pool: References Nether Devil pool
• size: 1 - Simple structure
• biomes: Nether biome tag
• land_search_direction: "HIGHEST_LAND" - Finds highest solid block
• Other fields similar to overworld

Note that the terrain flatness fields (terrain_height_radius_check, allowed_terrain_height_range) and project_start_to_heightmap are not read by the nether structure type. See Nether jigsaw structures for the full field reference.

Step 4: Create the Structure Set

File: data/mvs/worldgen/structure_set/nether_devil.json

{
  "structures": [
    {
      "structure": "mvs:nether_devil",
      "weight": 1
    }
  ],
  "placement": {
    "type": "moogs_structures:advanced_random_spread",
    "salt": 513238798,
    "spacing": 64,
    "separation": 16
  }
}

Nether Placement Characteristics

Spacing: 64 becomes ~106 chunks (~1700 blocks)

• Nether structures often use moderate spacing
• Nether is less crowded than overworld

Separation: 16 becomes ~26 chunks (~420 blocks)

• Lower separation than overworld
• Nether has more space

No Exclusion Zone:

• Nether structures typically don't need exclusion zones
• Less structure density in Nether

Field-by-Field Explanation

• structures: Single Nether Devil structure
• placement: Standard advanced random spread
  • salt: Unique identifier
  • spacing: 64, scaled to ~106 chunks
  • separation: 16, scaled to ~26 chunks

How Nether Placement Works

Nether structures use special algorithms:

1. Land Search scans the terrain column for a place to sit
2. Placement adjusts for the Nether's vertical nature
3. Structure Spawns on a suitable ledge or platform

Land Search Process

1. Structure attempts to spawn at chunk
2. Land search algorithm scans area:
   - HIGHEST_LAND: Finds highest solid block
   - LOWEST_LAND: Finds lowest solid block
   - FIXED_HEIGHT: Uses start_height directly
3. Structure placed at found location
4. Ledge offset applied if specified

Testing Your Structure

1. Create a new Nether world with your datapack/mod
2. Use /locate structure mvs:nether_devil in Nether
3. Verify:
   • Spawns in Nether biomes only
   • Places on suitable terrain (ledges/platforms)
   • Proper spacing between structures
   • Not in lava

Common Issues

Structure Not Spawning in Nether

Check:

• Using correct structure type (moogs_structures_generic_nether_jigsaw_structure)
• Nether biome tags are correct
• Structure set is configured correctly

Spawning in Wrong Locations

Solutions:

• Adjust land_search_direction (try LOWEST_LAND, or FIXED_HEIGHT to pin it to a set Y)
• Add ledge_offset_y for better positioning
• Use y_allowance to keep it within a height range

Advanced: Nether Jigsaw Structures

For expanding Nether structures:

Structure JSON:

{
  "type": "moogs_structures:moogs_structures_generic_nether_jigsaw_structure",
  "size": 5,
  "max_distance_from_center": 30,
  "land_search_direction": "HIGHEST_LAND",
  "ledge_offset_y": 3
}

Create Multiple Pools:

• Start pool
• Extension pools
• Branch pools

Add Jigsaw Blocks in NBT files to connect pieces.

Comparison: Overworld vs Nether

Feature	Overworld	Nether
Structure Type	moogs_structures_generic_jigsaw_structure	moogs_structures_generic_nether_jigsaw_structure
Land Search	Not available	HIGHEST_LAND, LOWEST_LAND or FIXED_HEIGHT
Ledge Offset	Not available	ledge_offset_y (optional)
Terrain Checks	Standard	Not available
Spacing	Varies	Often moderate
Exclusion Zones	Common	Rare

Best Practices for Nether Structures

1. Use Nether Structure Type - Always use moogs_structures_generic_nether_jigsaw_structure
2. Choose Land Search - HIGHEST_LAND for platforms, LOWEST_LAND for ground
3. Pin the height when it matters - use FIXED_HEIGHT for structures that need a set Y
4. Test Thoroughly - Nether placement can be unpredictable
5. Account for Lava - Use cannot_spawn_in_liquid: true
6. Consider Vertical Space - Nether is tall, structures can be vertical

Next Steps

Now that you understand Nether structures:

1. Complex Structure Example - Large expanding structures
2. Advanced Topics - More advanced features
3. Structure Files - Complete reference

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See Also:

• Structure Files - Nether-specific fields
• Template Pools - Pool system (same for Nether)
• Placement Systems - Placement configuration