{
    "feature": "tfg:moon/surface/pile/gabbro",
    "placement": [
        {
            "type": "minecraft:count",
            "count": 2
        },
        {
            "type": "minecraft:in_square"
        },
        {
            "type": "minecraft:heightmap",
            "heightmap": "WORLD_SURFACE_WG"
        },
        {
            "type": "minecraft:block_predicate_filter",
            "predicate": {
                "type": "minecraft:matching_blocks",
                "offset": [ 0, -1, 0 ],
                "blocks": [
                    "tfc:rock/raw/gabbro",
                    "tfc:rock/hardened/gabbro",
                    "tfc:rock/gravel/gabbro"
                ]
            }
        },
        {
            "type": "minecraft:in_square"
        },
        {
            "type": "minecraft:heightmap",
            "heightmap": "WORLD_SURFACE_WG"
        }
    ]
}