Vilya

=   Vilya
Base item	sapphire or brass ring
Affiliation	elves intelligent artifacts
When carried	none
When worn	standard effects for rings of that appearance up to 20 levels of study on each attack shock resistance warning stealth magical breathing
When invoked	none
Base price	0 zm
Weight	6

Vilya is an artifact that appears in dNetHack, notdNetHack and notnotdNetHack. It is unaligned and elf-favoring, and its base item is a ring with the randomized appearance of a "sapphire ring". If the sapphire ring is a ring of polymorph in the current game, then Vilya will appear as a brass ring instead.

Description

While worn, Vilya has the usual effects conferred by the ring whose appearance it matches, and additionally confers shock resistance, warning, stealth and magical breathing. Each attack made in melee or with a thrown/fired weapon while wearing Vilya applies 1d20 turns of study to the target, stacking with any existing study.

Wearing Vilya also massively lowers the failure rate of healing spells, guaranteeing the ability to cast any healing spell at 0% fail rate for almost any character: this does not supersede the inability to cast spells for other reasons, e.g. the influence of the Spire, lacking free hands, or any other effects that block all spellcasting.

In addition, wearing Vilya applies an intelligence-based modifier of ^(Int-11)⁄₂ to normal hit point regeneration, sanity regeneration, pet HP regeneration, and pet AC. This modifier can be negative, which will worsen each of these stats and can potentially kill pets if the modifier low enough, but the modifier will not cause negative hit point regeneration for the hero, and instead worsens existing regeneration to a minimum of 0 unless it was already negative.

Strategy

The effectiveness of all of the elf rings depends on their base item type in that game, e.g. Vilya is obviously much better in a game where sapphire rings are free action than in games where they are hunger. Despite this, Vilya is almost always worth wearing for characters with a free ring slot and decent intelligence.

Of the elf rings, Vilya is possibly the second-most useful for most characters: The study is effectively an untyped damage bonus for melee or ranged builds, and the boost to casting healing spells can be very helpful for any character that would struggle with them otherwise. With decent intelligence, the regeneration is also a nice side effect, but isn't really enough to save characters that are surrounded or facing monsters with high burst damage. The other resistances and intrinsics are mostly a nice benefit rather than anything essential, making it unlikely to be worth a wish but a nice find to encounter on the floor.

For Troubadours, this is possibly the best ring to have paired with a high intelligence stat, since it can seriously boost pets' defenses, healing them for up to 5-7 HP per turn even without trying to fully maximize intelligence. However, these characters are more likely to prefer Narya, as it scales off charisma (which Troubadors and other characters want to maximize for pet purposes) and provides more offensive boosts for pets.