Shopkeeper

A shopkeeper owns a shop and buys and sells the items within.

At first, shopkeepers seem skilled enough to prevent adventurers such as yourself from taking anything without payment. However, many NetHack players know where shopkeepers are vulnerable; if you do not, read on...

Normal transactions
Normally, shopkeepers own all items on any square of the floor of their shop, with the notable exception of the square adjacent to the door, here called the "entrance square". Here we make a distinction between:
 * the shop inventory, the items on the floor of the shop.
 * the shopkeeper's personal inventory, the items which the shopkeeper is carrying; this often includes several dangerous offensive wands.

If you pick up such an item, you will have a unpaid object in your inventory. Press [p] to pay for the items; the shopkeeper will ask you about each unpaid object, and if you pay, you will own the object while the gold will transfer to the shopkeeper's personal inventory.

If you drop an item onto the shop floor (not the entrance square), the shopkeeper might offer to buy it. If you refuse, or if the shopkeeper makes no offer, then you continue to own the item and can pick it up again without paying. However, if the shopkeeper forgets that you own the item, then the shopkeeper will start selling it.

Failed exploits
Here is a list of some ways that shopkeepers normally prevent you from taking their items without payment:
 * Use a charge from an unpaid item. The shopkeeper will charge a usage fee. You now owe the shopkeeper money, as if you were carrying an unpaid item. Shopkeepers also charge you for reading their spellbooks.
 * Try to walk out of the door with an unpaid item. The shopkeeper will stand on the entrance square, blocking your path. Because it is a door, you cannot walk through diagonally.
 * Use a pick-axe to dig a hole out of the shop. If the shopkeeper is adjacent, he or she will grab your "pack", thus taking everything in your inventory! This is punishment for making a hole in the shop floor.
 * Teleport some items out of the shop. The shopkeeper will charge you for the items, as if you now own them.
 * Walk out through a gap in the wall. Shopkeepers configure their shop walls to magically heal. Even if a dwarf or Umber hulk came by and left a gap while entering or exiting the shop, the gap will heal before you can exit the shop with your unpaid items.

Exploits that cause a police response
With certain items, you can successfully rob a shop, but the shopkeepers will summon Keystone Kops to attack you. The Kops will continue to spawn and attack you on that floor unless you genocide them or calm the shopkeeper.
 * Dig out of the shop with unpaid items. If you move away from the shopkeeper, then use a fast method, like a wand of digging, not a pick-axe, then you can escape a shop before the shopkeeper can move adjacent and intervene.
 * Teleport out of the shop. You just need to have some method of teleport, such as instrinsic teleport, a wand of teleport, or a scroll of teleport, ready to take you and your unpaid items out of the shop.

Successful exploits
To exploit shopkeepers successfully, without Kops chasing you, you need to know that shopkeepers give no attention to other monsters, including your pets.

What explains the reason why adventurers have such power to distract shopkeepers? NetHack never really explains how shopkeepers came to own shops in the dungeon. Maybe shopkeepers are former adventurers, or maybe they are servants of Moloch or the Wizard of Yendor. Maybe the DevTeam programmed too lazily.

In whatever case, all you need to do is to convince a monster or pet to carry items out of the shop. Then kill the monster, or let the pet drop the items, and you can take the items without payment or punishment.

However, convincing a monster or pet to actually carry out the item that you want can be difficult.

Shopkeepers are greedy!

 * Shopkeepers will own and sell anything on their shop floor. If you kill a monster in a shop, even if you had to kill it to save your own life, the shopkeeper will own both the dropped items and the corpse.
 * If you are hungry, shopkeepers charge more for food! (They even do this for corpses of monsters that you killed.)
 * Shopkeepers will reveal the identities of common weapons and armor when you buy or sell them. For example, if you sell a crude dagger, the shopkeeper will reveal that it was an orcish dagger. These identities are the same during every game. What shopkeepers never identify for you are scrolls, spellbooks, rings, or other such useful information. Shopkeepers also never tell you about BUC status or enchantment.
 * Shopkeepers will sell identified gems at high prices (as if all gems are valuable) while purchasing them at cheap prices (as if all gems are glass). So the most obvious way to identify gems by price does not work.
 * You can calm an angry shopkeeper by pressing [p]. If you have enough money, you can calm any shopkeeper!

Notable shopkeepers

 * Asidonhoppo
 * Izchak