{ "type": "minecraft:jigsaw", "biomes": "#minecraft:has_structure/trail_ruins", "step": "underground_structures", "spawn_overrides": {}, "terrain_adaptation": "bury", "start_pool": "minecraft:trail_ruins/tower", "size": 7, "start_height": { "absolute": -15 }, "max_distance_from_center": 80, "use_expansion_hack": false }