Credit cloning

The strategy of credit cloning is simple:

• Move all objects in the shop to a single pile. Drop a cursed item to prevent your pet from moving on to it, and engrave Elbereth in case monsters get spawned over times.
• Drop gold into the shop. The shopkeeper will give you credit for the gold.
• Let your pet steal the gold for you (a leash or magic whistle is very helpful here).
• Go to the pile and buy as much as you can from your credit.
• Sell all the recently bought items, even items that you own. It helps to put all the merchandise in single bag and drop it at once.
• You may need to buy and sell several times before you can exhaust your credit if you had a lot of starting credit.
• Drop the old + new gold in the shop and repeat from letting your pet steal it.

Repeat the technique till the shopkeeper has no gold--you will know this because the shopkeeper offers you credit instead of gold when you try to sell the item--and you have enough credit to buy everything that you want from the shop.

The technique is very time consuming and should not be done if you don't have slow digestion or a good amount of food. The slowest part is waiting for your pet to steal the gold, so a good starting quantity helps, too.

Credit cloning is more effective if you have a sack--or still better, a bag of holding. You can put all your gold into the sack, along with as many items as your pet can carry (preferably expensive ones). You can then have your pet carry the bag outside the shop and resell the items over and over to get all the shopkeeper's gold very quickly.

The point is to steal gold instead of merchandise, which has the highest weight-to-value ratio of all items in the game (except artifacts and identified gems) and is universally accepted. However, in the beginning, you might need to have your pet steal items.

The best shops for credit cloning, therefore, are ones with lightweight expensive items like rings, wands and identified gems. Delicatessens are probably the safest, because they stock food, but are also very time-consuming because the items are so cheap until you make much holy water. General stores are also good because you can sell many of your own items at the beginning, increasing the size of the initial pile of gold.

Using pets

Be careful that your pet doesn't starve to death while credit-cloning. If you are just starting a game and plan to credit clone, try not to let your pet pick up any items until you have reached a shop. By keeping the pet's apport from decreasing prematurely, you optimize its shoplifting ability.

Sometimes your pet will not pick up your "stealing bag" because it is too heavy. Base monster carrying capacity is equal to human maximum carrying capacity, or half human maximum if not strong. This is then modified by the ratio between the monster weights and human weights, except that strong monsters will always have a carrying capacity at least equal to the human maximum even if they are lighter than a human. Corpseless monsters are given a capacity proportional to their size instead of weight. Weight unit is 100 gold. Human maximum carrying capacity is 1000 units, and human weight is 1450 units. Among domestic animals, large cats, large dogs, ponies, horses and warhorses are all strong.

Pet type	Corpse	Can carry unassisted	in uncursed bag of holding	in blessed bag of holding
kitten	150	52	72	145
housecat	200	69	106	213
large cat	250	1000	1968	3937
little dog	150	52	72	145
dog	400	138	244	489
large dog	800	1000	1968	3937
pony	1300	1000	1968	3937
horse	1500	1034	2036	4073
warhorse	1800	1241	2450	4901

Using hostile monsters

Monsters which will pickup gold in shops
orcs
dwarves
centaurs
ogres
orc mummys
leprechauns

Certain monsters will pickup gold in a shop. These monsters will chase you into shops where you have left a pile of gold. Once they have picked up the gold, they will follow you out of the shop, where you can kill them, retrieve the gold, and repeat. Just as with pets, shopkeepers will show no alarm when these monsters swipe from them.

Some strategies for this:

• Whenever paying for anything in a shop, it is better to drop the money on the ground and pay out of your credit, rather than paying directly.
• When you are in the shop, the shopkeepers may stand on the square just inside the door and block the monsters from entering the shop. He will step aside from this square if you are in a direct line with it and at least a full square away from it.
• Some monsters, especially orcs and dwarves, will sense gold buried in the earth and loiter near it rather than following you to a shop. Dropping a trail of single gold coins will induce them to follow you.
• Occasionally a monster will have already picked up so much weight (rocks, armor) that they will not be able to pick up any gold.
• In a shop with gold on the floor, monsters may choose to chase and attack you, rather than picking up the gold. If you have placed the gold anywhere but in a corner, you can get them to follow you until they are standing on the gold. Move to a space where they are not in a direct line with you (e.g. a knight's move away.) They will then pick up the gold.
• Pets are actually a hindrence to this strategy; they tend to kill the monsters before the monsters have left the shop. So lock up your pets or strand them on an adjacent level.
• Orcish wizards may also swipe magical items as well as gold.
• Applying a figurine of a gold loving monster or casting stone to flesh on a statue of one inside of a shop is another method. Leprechauns are usually the only monster small enough to make transporting the statue feasible, however. This is of little use in Vanilla Nethack, but is one of the few ways to credit clone in the Black Marker in SLASH'EM.

SLASH'EM

Credit cloning is slightly more difficult in SLASH'EM than in vanilla, but also significantly more useful. The Shopkeeper services mean that it is useful to have credit in a shop even after the shopkeeper's gold has been exhausted and all useful items have been purchased. Pets are no longer guaranteed to pick up an entire pile of gold, so it is no longer possible to simply drop a pile of gold and have your pet kitten pick it up. It is necessary to place the gold into a sack or other container first. Fortunately, the shopkeeper identification service makes it much easier to identify valuable gems, and the massive increase in magic lamp price makes draining gold from shops quick if one is generated.