Similar to Stairhopping this technique consist on stacking three objects by a ledge so you can walk from your current floor to a lower or higher floor (there's no two second delay because of walking to the new floor). This is one way to kill creatures while receiving none or low damage. Other ways are shoothing a monster through a window or closing and opening a door. Parcels are normally used for weak monsters, but stronger monsters can move those, Ice Cubes or Pots are used instead.