waves:
    every:
        '3': feather, bone, stick
        '5': dirt:4, gravel:4, stone:4
        '10': iron_ingot:10, gold_ingot:8
    after:
        '7': minecart, storage_minecart, powered_minecart
        '13': iron_sword, iron_pickaxe, iron_spade
        '16': diamond_sword