Ring of regeneration
The ring of regeneration is an item in NetHack. While wearing it, a character heals more quickly but also becomes more hungry.
Identification
It is possible for a player to identify this ring by putting on the (noncursed) ring, throwing an object upwards <, and examining their healing rate. The normal healing rate without regeneration is some HP every few turns.
Dropping a ring of regeneration into a sink produces the message, "The sink looks as good as new."
Effects
The ring grants extrinsic regeneration. Regeneration causes you to heal one HP on any turn you would otherwise heal none. Regeneration is not cumulative, so wearing two such rings, or a ring along with another regeneration source, grants no further benefit.
Unfortunately, regeneration burns nutrition very quickly: every odd-numbered turn your nutrition is decremented. This is in addition to the standard nutrition cost of wearing the ring itself.
Strategy
Especially at very low levels, this ring is valuable because it makes much faster game play possible. The same thing goes for players who spend most of their time polymorphed, e.g. speed runners, because they naturally heal only one point per 20 turns. However, late-game characters with high experience levels and constitution have enough natural healing that regeneration becomes a minor benefit, making the ring a poor choice for the ascension kit.
Because of the increased hunger, a player should only wear one if he's hurt, or about to become so, or if he is satiated and wishes to become less satiated quickly to eat corpses for intrinsics.
