Requires:

"h_heatProof"
{
  "or": [
    {
      "and": [
        "Gravity",
        {
          "refill": [
            "PowerBomb"
          ]
        }
      ]
    },
    {
      "partialRefill": {
        "type": "PowerBomb",
        "limit": 6
      }
    }
  ]
}

Dev note: FIXME: The h_heatProof requirement is because Zeros only drop small energy, not enough to guarantee progress if the neighboring room is heated Later we should remove this in favor of some way to require that the neighboring room is not heated.