A Composite Entry is a powerful feature that allows you to group multiple entities or blocks into a single book page, or render custom scenes using NBT structures.

The individual components will automatically be removed from all categories.

You can define composites by creating a JSON file at: data/<namespace>/fieldguide/composites/<filename>.json

Standard Composites

For a single static scene, use structure_nbt or render:

{
    "values": [
        {
            "id": "minecraft:mangrove_propagule",
            "structure_nbt": "fieldguide:mangrove",
            "components": [
                "minecraft:mangrove_log",
                "minecraft:mangrove_leaves",
                "minecraft:mangrove_roots",
                "minecraft:muddy_mangrove_roots"
            ]
        }
    ]
}

Visual Variants (Multi-Image Composites)

If you want a single entry to feature multiple cycleable images or structures (e.g., grouping multiple mods' trees into one page), you can define an array of visual_variants:

{
    "values": [
        {
            "id": "fieldguide:palm_tree_group",
            "display": "minecraft:jungle_sapling",
            "components": [
                "biomesoplenty:palm_log",
                "beachparty:palm_log"
            ],
            "visual_variants": [
                {
                    "variant_id": "bop_palm",
                    "display_name": "Biomes O' Plenty Palm",
                    "structure_nbt": "biomesoplenty:palm_tree",
                    "components": ["biomesoplenty:palm_log", "biomesoplenty:palm_leaves"]
                },
                {
                    "variant_id": "beachparty_palm",
                    "display_name": "Beachparty Palm",
                    "render": ["beachparty:palm_log", "beachparty:palm_leaves"]
                }
            ]
        }
    ]
}

• id: The unique identifier for this custom entry.
• display: The primary entity or block ID to represent this entry in the UI.
• components: An array of entity/block/item IDs that make up this composite entry.
• structure_nbt / render: Used for a single-image composite.
• visual_variants: An array of variant objects that create interactive tabs on the entry page. Each variant needs a variant_id and display_name, plus exactly one display source:
  • structure_nbt and/or render: render a multi-block structure (as above).
  • entity: render a mob by its entity ID (e.g. "minecraft:husk"). Optionally add nbt (an SNBT string like "{IsBaby:1b}") to configure it.
  • block: render a single block by ID.
  • item: render an item by ID.
  • components (optional): the entity/block/item IDs belonging to this variant, used to unlock it when scanned. Defaults to the variant's entity/block/item (or its render blocks). Scanning any listed target unlocks that specific variant.

This lets you group mobs, blocks, and items from different mods/namespaces under one entry — for example consolidating several mods' palm trees, the maple-tree color variants of Biomes O' Plenty and Mystic's Biomes, or related mobs that other mods register as separate entities.

When a variant uses entity/block/item, its name, description, and loot are taken from that target automatically (so each grouped mob/block/item shows its own info instead of the base entry's). You can still override per variant with a custom in-book edit or the lang keys fieldguide.<type>.<path>.<variant_id>.description and fieldguide.name.<type>.<path>.<variant_id>.

{
    "values": [
        {
            "id": "fieldguide:zombie_family",
            "display": "minecraft:zombie",
            "components": ["minecraft:zombie", "minecraft:husk", "minecraft:drowned"],
            "visual_variants": [
                { "variant_id": "zombie",  "display_name": "Zombie",  "entity": "minecraft:zombie",  "components": ["minecraft:zombie"] },
                { "variant_id": "husk",    "display_name": "Husk",    "entity": "minecraft:husk",    "components": ["minecraft:husk"] },
                { "variant_id": "drowned", "display_name": "Drowned", "entity": "minecraft:drowned", "components": ["minecraft:drowned"] }
            ]
        }
    ]
}