Farming is any kind of repetitive behavior which is felt to be against the spirit of the game. This definition does not tie down exactly what behaviors count as farming, as opinion varies.
Hanging around an altar sacrificing anything that comes along is a natural part of many legitimate games of NetHack, but some feel that taking this to extremes is scumming.
Advancing your character to the point where black puddings pose no threat, then carefully using weak weapons to divide them without killing them allows players to "farm" as many puddings as they wish. The puddings can be killed to get a death dropped item, and their corpses can be sacrificed for a variety of benefits.
Players can continue this process (and even automate it) until they possess thousands of hit points, AC:-128, and hundreds of wands of wishing.
While gremlins normally stop dividing once their hit point maximum falls to 1, it's possible to induce them to divide indefinitely by using a ring of conflict. This works because whenever a gremlin kills something, such as another gremlin, its hit point maximum is increased, which allows it to divide again. Since on average a gremlin gains more than one maximum hit point when it kills another gremlin, the result, provided that the gremlins are given enough time to heal and divide, is a net increase in the number of gremlins. As gremlin division does not respect extinction, this allows gremlins to be farmed somewhat like puddings.
To breed gremlins effectively, the following steps are advisable:
- Use an open, watery level. You need lots of pools for the gremlins to divide in, and an open area for conflict to be most effective.
- Try to keep the level clear of other monsters and traps. Remember that fully divided gremlins only have one hit point, and therefore die very easily.
- Don't keep the ring of conflict on all the time. Instead, only put it on for one turn, take it off again immediately, and wait several turns for the surviving gremlins to fully heal and divide before putting it on again. This also keeps you less hungry and the gremlins less vulnerable to attacks by other monsters.
- Obviously, don't do this at night. Even if you stand on Elbereth or a scroll of scare monster, the gremlins will still sometimes hit you when you wear conflict.
- Looting a throne while confused will generate one throne room monster (if you are confused and no chest is on the level). You can generate an indefinite amount of monsters this way: the throne is never destroyed, a forgotten spell is an unlimited source of confusion, only some monster species will respect extinction, and you even get your gold back from the monsters. Dragon scales, lots of potions and scrolls, and death drops can be had. You might want to engrave concentric circles of Elbereth this way to protect yourself from ranged attacks.
Illiterates can polymorph into a ghoul, stand on a scroll of scare monster, and confuse themselves with a cursed unicorn horn. In principle, this is possible without polyself, but unattended copy-paste farming loses its power. The chance of death to sickness is under 2/10000000000000 if immediately applying a blessed horn until cured. If you demand at least 99.5% survival rate in 20 000 turns, the cycle "1x cursed, 5x#loot, 8x blessed, unbag $15" is near-optimal, but you generate only 721 monsters. For comparison, forgotten spells allow some 13000 monsters.
Kraken can be killed trivially when on dry land, and their corpses can be revived using undead turning. This means you can continue killing the same monsters indefinitely, racking up a very high score with very little effort.
You can also trap kraken (which are MZ_HUGE, and so can't squeeze through a diagonal) by digging walls in the following pattern:
# # # # # # #;#;#;#;#;#;# #;#;#;#;#;#;# #;#;#;#;#;#;# #;#;#;#;#;#;# # # # # # #
Characters with a source of reflection and the stone to flesh spell can easily stone and revive Medusa as many times as they like. No death drops are generated this way, but it does provide an easy source of experience points.
This is only borderline scumming, as any character capable of doing it is more than capable of ascending. The goal might be to gain large numbers of exotic items to ascend with, to gain billions of points, or (more commonly) to impress onlookers.
- Eat rings of increase damage until you have a high enough intrinsic damage bonus to kill Death in one hit (+60 should work).
- Clear the Astral plane of all distractions.
- Increase your polearm proficiency to skilled.
- Trap Death in a corner on the Astral plane, like so:
---- |&j |jO@ |jj
In this example, Death is trapped between blue jellies and a boulder. He cannot move, but you can hit him with a polearm while he is in line of sight. Once he's dead (in one hit), attempt to push the boulder over his corpse. This will revive him. You can then repeat the procedure. You can work out the exact sequence of key strokes used in a complete cycle of this process (in this case, for example, "aahy.jyk"), and copy this line a few thousand times in a text editor, then paste the whole lot into the NetHack interface.
The result will be many thousand death-dropped items and a very high score. If the number of death-dropped items exceeds 32,767 on the same square, the game will probably crash, so periodically checking Death's square and redistributing the items (possibly by teleporting them away, or polymorphing them together) is necessary. This is due to the fact that the number of items present on a square is stored in a signed short when the items are listed.
First, retrieve the Book of the Dead. This works best if you refrain from killing the Wizard, because then he won't randomly appear until you perform the Invocation Ritual. Reading the cursed Book can summon wraiths (as well as other undead, including liches, so genocide what you cannot deal with). However, it also marks the current level as a graveyard. This means that you should lead wraiths to another (nongraveyard) level before killing them for their corpses. Recall that eating a wraith corpse at experience level 30 will still increase your maximum HP and power.