{
  "name": "lava_plus_water_makes_steam",
  "description": "Lava and water adjacent should produce steam and stone",
  "seed": 42,
  "init_mode": "empty",
  "setup": [
    {"type": "fill_rect", "x": 100, "y": 115, "w": 20, "h": 1, "material": "stone"},
    {"type": "fill_rect", "x": 100, "y": 100, "w": 20, "h": 1, "material": "stone"},
    {"type": "set_cell", "x": 105, "y": 110, "material": "lava"},
    {"type": "set_cell", "x": 106, "y": 110, "material": "water"}
  ],
  "steps": 15,
  "assertions": [
    {"type": "no_material_in_region", "x": 100, "y": 105, "w": 20, "h": 10, "material": "lava"}
  ]
}