Many damaging corpses do not cause their usual damage if tinned; normally, Z and M are sickening to eat, but they become edible when tinned. This is because tins cannot be tainted, and the taint in the zombie and mummy corpses is removed by the tinning process. Poisonous and acidic corpses are also rendered harmless. However, corpses which turn you to stone, turn you to slime, stun you or cause you to hallucinate will still have the same effect when tinned. Additionally, tins of corpses will provide the same intrinsic as a corpse alone. This makes them quite useful when working with giants and dragons, and for keeping tengu corpses to eat once you have a ring of teleport control to avoid getting uncontrolled teleportitis. It should go without saying, but if eating a corpse is cannibalism, eating a tin of that corpse is too. Tinning dwarf zombies or dogs doesn't make eating them less bad if you are a dwarf.
Tins made from a tinning kit always have the same BUC status as the tinning kit, and are either homemade or rotten; its status as homemade or rotten is determined when the tin is eaten. Blessed tins can be opened in one turn. Uncursed tins are occasionally rotten and cursed tins always are. Homemade tins of foo only have 50 nutrition, making it possible to consume several giants or dragons without becoming satiated. Rotten tins provide negative 50 nutrition.
An uncursed tinning kit is included in the starting equipment of the Archaeologist, containing 30 to 99 charges.
Tinning kits only have a limited number of charges, and may need to be recharged after much use. See Charging#Tinning kit for more details.
There are many situations in which tinning a corpse is a good idea.
- As an Archaeologist, food is sometimes scarce at the start. It may be worth tinning small monsters to raise their nutrition until a good supply is secured. Soldier ants, Sewer rats, Rock moles, Ravens, Rabid rats, Newts, Killer bees, Iguanas, Green molds, Giant rats, Giant beetles, Giant ants, Geckos, Floating eyes, and Brown molds are all prime early candidates where tinning will raise their nutrition at the risk of being rotten, until you can get the kit blessed.
- If you are too full to eat them soon, tin monsters which may grant intrinsics you don't have yet to save them for later. Similarly, tinning giants is useful because they boost strength.
- You may also want to tin intrinsic-granting corpses when you already have the intrinsic in case you lose it. This is particularly useful with dragons and floating eyes which are guaranteed to grant their respective intrinsics.
- As discussed above, poisonous and sickening corpses become safe to eat when tinned.
- Tin tengu and eat them once you have a ring of teleport control (or a farily large number) for the intrinsic because they might give you teleportitis instead, if you do not want that. Similarily, in that case, eat leprechaun and nymph tins only after getting extrinsic or intrinsic teleport control.
- Tin an invisible stalker and eat it once you have some means of becoming invisible, even if temporarily. You will gain the invisibility and see invisible intrinsics permanently from one meal.
- A blessed tin of nurse meat will restore you to full health in two turns. But be warned - for humans, this is cannibalism.
- Tinning a troll is a good way to keep it from reviving; this is especially useful on the Barbarian quest.
- A blessed tin of acid blob (or other acidic monster) always opens in one turn and can save you from stoning. The acid damage is removed by the tinning process, but the unstoning properties of the acid are NOT. Note that while a cursed lizard corpse or a cursed potion of acid will still work, a cursed tin of acid blob meat can take a long time to open, far too long to use in emergencies. Therefore it is important to track the tins' BUC if you go this route.
- Tinning can be performed while riding so you don't need to dismount to eat corpses. This can be important if you are not a knight, the corpse is too heavy to carry and your steed is difficult to keep tame (i.e. Ki-rin).
Consider tinning named monsters and keeping them as trophies. A tin of Medusa or Wizard of Yendor meat is a pleasant item to find in your inventory.
Tinning kits are not considered magical tools when polypiling.
Tinning in the Real World
NetHack's tinning kit is not considered a magical tool for purposes of polymorphing, but it is hard to say what kind of non-magical object(s) in the real world it is meant to correspond to. Home canning of meats is a fairly laborious process that involves cutting the meat into appropriate pieces, usually salting and partially cooking it, packing it into containers and then boiling the containers in a pressure cooker for over an hour. The pressure cooker is needed to raise the cooking temperature above 100 degrees C (212 degrees F), to eliminate dangerous microbes. This corresponds to the concept in NetHack of tinned food not rotting away. Home canning uses screw-top glass jars, but the NetHack tinning kit obviously uses tin cans, which further adds to the complexity, as the cans must be sealed. This is probably done by soldering the top onto the base, as was originally done with tin cans in our world. Canning guidelines from the United States Department of Agriculture are here. So, we can assume that the NetHack tinning kit includes the following:
- A large number of tin cans.
- Soldering supplies (presumably).
- A knife or knives for preparing the meat.
- A pressure canner.
- A good heat source, such as a propane burner, and fuel.
- Tongs, silicone gloves, or some other implements for handling the hot containers.
- (Maybe) salt.
- (Maybe) a frying pan, or some other implement for pre-cooking the meat.
The length of turn in NetHack is fairly abstract and flexible, and attempts to work this out will yield different results based on what kinds of activities (movement, combat, etc.) are used to calculate it. But, in light of the above, tinning a corpse is clearly one of the most action-packed turns a player will ever experience.
However, it never hurts to remember that NetHack is not real life.
- apply.c, line 1425
- "This occurs because (cprefx in eat.c) cures stoning and is called by the corpse-eating code and tin-eating code, whereas stomach acid is handled by (eatcorpse in eat.c) which is not invoked for tins." (Killian) See talk page.