[
  { 
    "mob": [  
      "minecraft:zombie" 
    ],
    "persecond": 1.0, 
    "attempts": 5, 
    "amount": { 
      "minimum": 1, 
      "maximum": 2 
    }, 
    "conditions": { 
      "dimension": "minecraft:overworld", 
      "mindist": 20, 
      "maxdist": 60, 
      "norestrictions": true, 
      "maxthis": 20,
      "minheight": 64
    } 
  } 
]