{
    "minecraft:skeleton_skull": 0,
    "minecraft:skeleton_wall_skull": 0,
    "minecraft:wither_skeleton_skull": 1,
    "minecraft:wither_skeleton_wall_skull": 1,
    "minecraft:zombie_head": 2,
    "minecraft:zombie_wall_head": 2,
    "minecraft:player_head": 3,
    "minecraft:player_wall_head": 3,
    "minecraft:creeper_head": 4,
    "minecraft:creeper_wall_head": 4,
    "minecraft:dragon_head": 5,
    "minecraft:dragon_wall_head": 5
}