Corpses dropped by mummies take much longer than other corpses to rot away, since they are all dried out. (They are still unsafe to eat and unable to be sacrificed from the moment they drop, though.)

Add more sources of nausea, particularly in the late game, because it’s an underutilized debuff that only really is relevant early. Proposed sources:

• Certain types of demons or the presence of certain demon lords such as Baalzebub or Juiblex.
• When you are hit with a disease attack but for some reason don’t get deathly sick, or are already deathly sick.
• Stepping over a rotting corpse.
• Some smallish chance every turn you are in a cockatrice nest.

Most of these increased sources of nausea should be subjected to some sort of (low-chance) Constitution saving throw so that characters with better Constitution have an advantage.

The corpses of monsters killed by cold effects take longer to rot. (Maybe they should also be fresh for sacrifice longer than usual.)

Sharply cut the frequency of lizards spawning (possibly even lower than 1/7), and possibly remove the special case that makes them always leave a corpse. This is because a player will usually accumulate enough of their corpses to be easily safe from any delayed stoning effect for the whole game. This won’t much affect reverse genociding them, if the player really wants a lizard corpse.

Also, possibly elevate their monster difficulty to something higher than 6; not because they are that difficult, but to make them appear only later on in the dungeon.

Alternatively, simply make lizard corpses rot, so that a player who wants to carry around a stoning defense must use other items, such as tins of lizard or acidic monsters, or potions of acid.

When generating a corpse during level creation, pre-age the corpse a la zombie and mummy corpses so that it’s not weirdly fresh.

Meatballs, meat rings, meat sticks, and huge chunks of meat all become possibly tainted at the same age as corpses.

Almost-rotten corpses, those that give the “You feel sick” message, may cause you to vomit.

Skeletons for vertebrate monsters. Corpses turn into these when they rot away. They cannot be undead turned into their monster; trying to do this will create a skeleton monster instead. Lawfuls might get an alignment boost for burying a skeleton in a pit and filling it.

Fountains can be contaminated by letting corpses rot on top of them. This makes them more dangerous to use.

All acidic corpses, not just acid blobs, never get tainted (but do eventually rot away).

Mummy corpses never rot away.

Unicorn corpses are never tainted from age, though they do eventually rot away.

Zapping a corpse with a cold ray will increase its decomposition timer (making it take longer to rot). If already rotten, only scales it back to rotting age.

Ideas around a system in which you can cook corpses:

• The general idea is to unbreak the hunger system by making regular corpses unsafe to eat, so the shortage in resources isn’t in food itself but is in safe methods of cooking it.
• Cooking sets a corpse’s rot timer to 0, lets them go longer without spoiling, or unspoils them.
• May also remove poison from some kinds of poisonous corpses.
• Cooked corpses are unsuitable for sacrifice and less likely to give intrinsics, or don’t at all (because the vitamins are destroyed).
• Can apply wands of fire to cook corpses.
• Or maybe eating raw non-vegetarian corpses is just plain dangerous, causing vomiting or sickness or other bad effects.
• Corpses can be cooked by killing monsters with fire or hitting monsters with fire attacks while they are carrying corpses.
• The problem is that nobody has yet proposed a mechanism for cooking corpses that would work well. Having firewood or some similar thing would massively affect the early game between characters that can and cannot manage to find it, and roles that start with or without it. Wands of fire have been proposed as a resource but those are valuable. Introducing a new item like firewood means that a whole lot of mechanics have to be reviewed for whether they should interact with or create that item.

Blessing a corpse prevents it from being tainted or rotten (the “Blecch! Rotten food!” effect).