The Eyes of the Overworld
|( The Eyes of the Overworld|
|Base item||pair of lenses|
|Base price||2500 zm|
While wearing the Eyes you are granted astral vision: the squares around you are illuminated as would be lit by a lamp. The difference is astral vision penetrates walls, doors, solid rock, and any other obstruction. Objects seen through astral vision using the farlook command are described as though you had personally handled the item (a behavior similar to a blessed potion of object detection; for example, viewing a scroll on the floor will tell you its label, not merely "a scroll," and gems discovered embedded in rock will appear with whatever type-name you might have given them. This is highly useful in trying to find secret doors or trying to navigate Gehennom without magic mapping.
The Eyes also provide magic resistance when worn. Prior to version 3.6.0, the Eyes provided magic resistance when simply carried.
Invoking the Eyes provides enlightenment. You can use this as a semi-reliable method to identify rings and amulets (the only problem is when you try to identify a ring that provides an intrinsic you already have, such as stealth).
While wearing the Eyes, blindness from any source will not obstruct your vision; internally, the game tracks the duration and cause of your blindness, but all effects of those status ailments are overridden by astral vision (similar to Grayswandir's behavior with hallucination). Because Nethack assumes LOS is symmetrical — that is, if you have a clear line of sight to a monster, it can see you too — monsters are capable of using gaze attacks through walls and other obstructions as long as you are presently viewing them through astral vision (that is, if they are within a three-tile radius while you are wearing the Eyes). This can be lethally tragic when dealing with Medusa, or if a pesky umber hulk on the other side of an unphaseable/undiggable wall repeatedly confuses you. In such cases, it may be necessary to temporarily remove the Eyes, as astral vision becomes a liability instead of a boon.
The Rogue level
Astral vision does not grant its "vision" properties while on the Rogue level; monsters, tiles, and items are not revealed through darkness or obstructions. The only parts of it that still function are those that prevent and override blindness.
The Eyes of the Overworld is a 1966 novel by Jack Vance, part of his Dying Earth series, which was highly influential on D&D (but not NetHack itself so much). The anti-hero Cugel, a resourceful but amoral rogue, is tasked by a wizard to obtain the titular artifact (essentially, rose-tinted contact lenses) from a squalid village whose "aristocracy" wears the Eyes, which allow them to see everything around them as though it were opulent luxury.
... and finally there is "the Eyes of the Overworld". This
obscure artifact pushes the wearer's view sense into the
"overworld" -- another name for a segment of the Astral Plane.
Usually, there is nothing to be seen. However, the wearer
is also able to look back and see the area around herself,
much like looking on a map. Why anyone would want to ...