{
  "type": "minecraft:fossil",
  "config": {
    "max_empty_corners_allowed": 4,
    "fossil_structures": [
      "minecraft:monster_room/default",
      "minecraft:monster_room/default",
      "minecraft:monster_room/default",
      "minecraft:monster_room/default"
    ],
    "overlay_structures": [
      "minecraft:monster_room/zombie",
      "minecraft:monster_room/zombie",
      "minecraft:monster_room/skeleton",
      "minecraft:monster_room/spider"
    ],
    "fossil_processors": "minecraft:mossify_50_percent",
    "overlay_processors": "minecraft:mossify_50_percent"
  }
}