FearFactory/1.20.1-FearFactoryTest/minecraft/config/alexsmobs/skreecher.json

{
  "biomes": [
    [
      {
        "type": "BIOME_TAG",
        "negate": true,
        "value": "forge:no_default_monsters"
      },
      {
        "type": "BIOME_TAG",
        "negate": false,
        "value": "alexsmobs:skreechers_can_spawn_wardens"
      }
    ]
  ]
}