[
  {
    "id": "fd_crawling_darkness",
    "looks_like": "fd_darkness",
    "type": "field_type",
    "intensity_levels": [ { "name": "darkness", "move_cost": 2, "light_override": 0.0, "translucency": 100 } ],
    "half_life": "5 minutes",
    "percent_spread": 50
  }
]
