The ring of warning, and only that, should indicate the exact amount of turns you have left to live when afflicted by a timed instadeath such as sliming, stoning, or strangulation. (And drowning and other forms of suffocation in variants that have that.) This feedback is conveyed by the ring vibrating that number of times, e.g. “Your [ring] vibrates twice.” Possibly it should only happen when the amount of turns to live is low because it doesn’t make that much sense for it to vibrate 20 times in one turn and have the hero count that accurately.

Being choked and unable to breathe should confer all the benefits of being unbreathing, including being (partially) immune from the effects of poison gas.

Being strangled for more than a couple turns starts to reduce your Constitution (or maxHP).

Add a new damage type AD_CHOK, for specific suffocation attacks (so that rope golems’ AT_HUGS AD_PHYS combination doesn’t have to be interpreted as choking).

Artifact chaotic amulet Amulet of Splendor: provides every single amulet effect, as well as unchanging-ignoring controlled polyself when invoked. Wearing it conveys life saving (this WILL disintegrate the amulet if triggered), magical breathing, unchanging, poison resistance, ESP, reflection, strangulation (doesn’t kill you due to magical breathing but maybe it makes it so you can’t eat food or something while wearing it, or it autocurses), restful sleep, and gender change for as long as you wear the amulet. Base type is a cheap plastic imitation of the Amulet of Yendor.

Implement a strangulation or “can’t breathe” timer, which unifies strangulation, suffocation, food choking, rope golem choking, and drowning, and also provides a clean way for monsters to have a suffocation attack.

• This means that choking over food is no longer instantaneous. Each turn while choking over food, you have a 20% chance of vomiting and lose 1000 nutrition. At certain points while the strangulation timer is getting closer to 0, you take one point of Con damage.
• Drowning monsters now grab and pull you underwater in 1 turn, but you have until the timer runs out to kill the monster or escape in some other way. Lifesaving while drowning does not give you a free escape, but resets the drowning timer.
• Rope golems are now more dangerous, since they represent a delayed instadeath.