Zork Zero/Dead ends

Things which should you try, will make it impossible to finish Zork 0.
 * Open the nut away from the Jester.
 * Wear out the magic wand (use 5 times) before needed.
 * Drink all (4 times) of the magic potion before needed; you can spill it accidentally by typing "drop potion" instead of "drop cup". It will be also spilled if you fall down the gravel pit from the Grotto.
 * Break a weight of the Tower of Bozbar game (by putting a heavier one over a lighter one).
 * Teleport on the Island while the Yacht or Dirigible is not docked there.
 * Let the fox, the chicken and the worm eat each other.
 * Enter the Inquisition by having the magic Cloak in your inventory (it will be taken, and if you survive you won't have it back).
 * Fail to take the box from the Inquisition (you won't be able to enter the hall after you leave).
 * Drop any usable item in the Pits or in the Cauldron.