Ring of polymorph
A ring of polymorph is a type of ring that appears in NetHack.
Contents
Generation
The ring of polymorph is generated as cursed 9⁄10 (90%) of the time, and is otherwise generated uncursed.
General stores and jewelers shops can sell rings of polymorph.
Wizards may be given a ring of polymorph as one of the random rings in their starting inventory, though they will never start with a means of polymorphing and a ring of polymorph control simultaneously.[1]
Description
While worn, a ring of polymorph grants polymorphitis, which has a 1⁄100 chance of polymorphing the character each turn: this polymorph can also fail and induce system shock unless the character has polymorph control, or else is wearing dragon scales or dragon scale mail. Eating the ring has a 1⁄3 chance of giving the character intrinsic polymorphitis. Monsters will never wear this ring - any monster that randomly polymorphs constantly is usually a shapechanger such as a chameleon.
If a character has polymorph control, they may choose the form they change into whenever the ring would polymorph them. For characters afflicted with lycanthropy, the ring of polymorph will instead trigger a change from their normal form into the animal form of the werecreature that infected them, or vice versa; polymorph control will prompt with the option to accept or decline the change. If a character is wearing an amulet of unchanging, the ring of polymorph will have no effect beyond ring hunger.
Dropping the ring into a sink will turn the sink into an altar (of random alignment), a fountain, a grave, or a throne, with an equal probability of each (25%).[2]
Strategy
The ring of polymorph is one of several reasons that wearing unidentified rings randomly is a Bad Idea: even when uncursed, wearing one for any extended period of time may result in you shifting into a form that removes or breaks armor, has low carrying capacity or (worse yet) leaves you with no hands to remove the ring. For characters that have an uncursed and identified ring, however, they can pair it with a ring of polymorph control to take on powerful monster forms for various purposes. See the strategy section on the polymorph control article for the various forms available.
Characters who have not yet discovered a wand of polymorph or else wish to reserve wand charges for polypiling can make use of both rings, saving polymorph traps for pets if they wish. For cautious players, controlled polymorphing using these rings can be reserved for specific circumstances, e.g. while locked within a co-aligned temple with a stash. Additionally, characters that lack altars or other conveniences from dungeon features (such as a fountain or throne) can try to transform sinks by dropping the ring down them.
Identification
Informally identifying the ring of polymorph can be fairly difficult - wear-testing is very risky compared to other price-identified 300zm rings, as an especially unfortunate character may find themselves quickly polymorphed with their valuable armor broken. While it is more likely to be cursed than other rings priced at 300 zm, this is by no means guaranteed.
In addition to ruling out the ring of conflict by wearing the ring near relatively weak and/or peaceful monsters, you can also rule out the ring of teleport control using a teleportation trap.
The odds of a ring that is price-identified and tested for beatitude being a ring of polymorph is given in the following table:
| Testing done | Any BUC | Non-cursed | Uncursed | Cursed | Blessed |
|---|---|---|---|---|---|
| Any price | 3.45% | 0.50% | 0.52% | 10.14% | 0% |
| 300 zm | 25.0% | 3.6% | 3.6% | 75.0% | -- |
| 300 zm, not telecontrol nor conflict | 50.0% | 10.0% | 10.0% | 90.0% | -- |
History
The ring of polymorph first appears in NetHack 2.2a along with the ring of polymorph control.
The effect of dropping the ring down a sink is introduced in NetHack 3.6.0, and is integrated from UnNetHack. In NetHack 3.4.3 and previous versions, including some other variants based on those versions, the game will instead print a message with no other effect:
- The sink looks momentarily like a fountain.
Messages
- The sink transforms into a <feature>!
- You dropped a ring of polymorph down a sink, turning it into a different dungeon feature, and you are not blind.[2]
Variants
Many variants often add new dungeon features, including ones that a sink also can be transformed into by dropping a ring down one; the probability of a sink turning into a given dungeon feature remains equal for each one.
dNetHack
In dNetHack, the various artifact rings - Lomya, Vilya, Nenya, Narya, the Ring of Thror, and the Shard from Morgoth's Crown - have generation rules that prevent them from using the appearance of a ring of polymorph.
