ZenXArch's Zombie Apocalypse

Changes

• Added drowned outer layer to rain zombies
• Now you can add outer layer to zombies
• For example

"zenxarch:overlay": {
      "layerId": "minecraft:drowned",
      "layerName": "outer",
      "texture": "minecraft:entity/zombie/drowned_outer_layer"
    }

This will attach a zombie renderer that renderers entity model layer "drowned/outer" with texture minecraft:entity/zombie/drowned_outer_layer