onEvent('worldgen.remove', event => {
  event.removeOres(ores => {
    ores.blocks = [ 'extcaves:oldstone', 'extcaves:brokenstone', 'extcaves:sedimentstone', 'extcaves:dirtstone', 'extcaves:dirtstone_cobble', 'extcaves:marlstone_powder', 'chisel:marble/raw', 'chisel:limestone/raw', 'chisel:basalt/raw' ] // Removes these blocks from worldgen
  })
})