The foodless conduct restricts eating in any form. This includes noncomestible items, such as rings and amulets, walls, doors, and boulders, if you happen to be polymorphed into a creature that can eat such things.
For non-eating monsters, see inediate.
Breaking the conduct
The following activities break the foodless conduct:
- Eating any item with the e command.
- Eating the brain of a monster while polymorphed into a (master) mind flayer.
- Engulfing a monster while polymorphed into a digester.
- Chewing through a wall while polymorphed into an Umber hulk
The following activities do not break the foodless conduct:
- Quaffing a potion (even fruit juice, booze, or water).
- Attacking while polymorphed into a vampire so as to drink blood. This will only give nutrition in SLASH'EM, however.
- Receiving nutrition from your god by Praying when Hungry or worse.
A player starts at nine-hundred nutrition. This means, without any aid or penalties, a player begins fainting at approximately turn 900 and starves soon after. Wearing a ring of slow digestion reduces nutrition consumption to 5% of the natural rate. So if you put on a ring of slow digestion on turn one, you will last approximately 18000 turns before fainting, which, if you're fast enough, gives you plenty of time to ascend. However, only wizards have a chance at starting with slow digestion, making this option less viable.
Other than the passage of turns, non-hungerless spellcasting, jumping, carrying the Amulet of Yendor, wearing rings and amulets, attacking, attempting to displace pets, and being Stressed or worse all consume additional nutrition. See the nutrition article for more information about what consumes nutrition points.
The following activities restore nutrition to some set amount:
- Praying while Hungry or worse may restore your nutrition to 900. It is normally best to wait until Weak; being Weak or worse is considered a major problem and if prayer works at all it will cure your worst major problem.
- Activating an amulet of life saving with less than 500 nutrition restores your nutrition to 500.
- Polymorphing into your own race sets your nutrition to 499 + 1d500.
Polymorph control works even when fainted. A constitution 18 character has only a 0.15% chance of starving before polymorphing if he puts on both rings after getting hungry. At con 3 it is 2.36% chance.
The following activities increase your nutrition level without breaking foodless:
- Quaffing a potion of booze or undiluted fruit juice restores 30 nutrition if blessed, 20 if uncursed, 10 if cursed. Half if diluted fruit juice.
- Quaffing an uncursed potion of water restores 1d10 nutrition.
Any potion except for a potion of acid can processed: Dilute it, dip a large stack of water into anything else for a 1/4 chance of sickness, convert to fruit juice by cancelling with a wand, spell or dipping a unicorn horn, and optionally alchemize with speed for booze to double its nutritional value.
When to pray
Successfully praying and having your hunger cured restores your nutrition to 900 points. If you pray after 900 turns when you're hungry again, the prayer will succeed if your prayer timeout was less than 1100. Your prayer will fail with a ~7% chance. If instead you spend some turns in the Fainting state, until 1200 turns have passed since your last prayer, and only then pray, you will succeed if your prayer timeout was less then 1400. Now your chance of failure is only around 2%.  Thus if your foodless strategy relies on repeatedly praying for food (until you find a ring of slow digestion), you should consider finding a safe place to faint to increase your odds of succesfully praying.
Ways to keep your nutrition high include:
- Wearing a ring of slow digestion.
- Not jumping and not wearing rings and amulets.
- Avoiding spellcasting unless you have hungerless casting.
- Abusing the dual ring of slow digestion bug.
- Manipulating hunger checks in other ways (such as dropping the Amulet of Yendor every twenty turns on a specific turn number).
- Polymorphing into a monster that does not eat, probably wearing an amulet of unchanging.
- Sleeping reduces nutrition consumption to approximately 10% the natural rate.
- Don't melee-fight or displace pets. Both cost 1 turn's worth of nutrition, including ring hunger.
Other than the obvious problem of avoiding starvation, foodless is difficult because eating corpses is the most popular way to gain important intrinsics like poison resistance and telepathy. One technique to address this is to ascend a monk, who attain most of the important intrinsics from gaining experience levels.
Here are other techniques to gain important intrinsics.
Fire resistance is much less urgent if you detect and avoid fire traps, e. g. with the detect unseen spell or the PYEC and a crystal ball. Spellcasters (especially Wizards with hungerless casting) can simply use skilled monster detection to substitute for telepathy.
Once you have reflection, can reliably avoid traps, have poison resistance, and have free action, the other resistances can generally be missed just fine.
Ascending so quickly that nutrition never falls low enough to become a problem.
Not using any amulets of life saving to restore hunger.
Dual slow digestion
Abusing the dual ring of slow digestion bug to, ideally, never lose any points of nutrition.
- Robert R Schneck describes his liquid diet foodless, atheist, true polyselfless, survivor tourist here on RGRN.
1.2% of all winning accounts on NAO have a foodless ascension.
- pray.c in NetHack 3.4.3, line 306
- end.c in NetHack 3.4.3, line 417
- polyself.c in NetHack 3.4.3, line 189
- potion.c in NetHack 3.4.3, line 506
- potion.c in NetHack 3.4.3, line 570
- potion.c in NetHack 3.4.3, line 452
- eat.c in NetHack 3.4.3, line 2130