Xorn

X xorn
Difficulty	11
Attacks	Claw 1d3, Claw 1d3, Claw 1d3, Bite 4d6

X xorn
Difficulty	11
Attacks	Claw 1d3, Claw 1d3, Claw 1d3, Bite 4d6
Base level	8
Base experience	139
Speed	9
Base AC	−2
Base MR	20
Alignment	0 (neutral)
Frequency (by normal means)	1 (Very rare)
Genocidable	Yes
Weight	1200
Nutritional value	700
Size	Medium
Resistances	Fire, Cold, Stoning
Resistances conveyed	None
A xorn: can phase through walls. does not breathe. has a thick hide. can eat metal. is normally generated hostile. is strong.
Reference	monst.c#line2054

The xorn is a monster that appears in NetHack. It is the only member of the ​X xorn monster class.

The xorn is notable for its ability to phase through walls and eat metal. Xorns are also unbreathing and resistant to fire, cold, and stoning.

Xorns are kebabable, granting a +2 to-hit bonus when using a weapon that uses the spear or javelin skills against them. They are also susceptible to digging attacks, granting a +2 to-hit bonus to when using pick-axes or dwarvish mattocks to attack them.

Generation

Xorns are rarely randomly generated, and typically will not be encountered until the Castle, where at least one xorn will appear.

Xorns are the second quest monster for the Monk quest and Wizard quest; they also function as the Monk's second quest monster "class", and are thus slightly more common for them than Wizards.

Xorns can also be generated on the Plane of Earth by digging with a pick-axe.

Strategy

Xorns have a decent AC of −2 and four attacks including an extremely nasty bite, and their phasing can make them difficult to evade; however, they move at a slow 9 speed and respect Elbereth. Thanks to this behavior, they can be dispatched with sufficient caution – however, players should not use non-disposable iron projectiles against xorns. Xorns can be lethal to players with low AC who try to out-melee them, particularly Monks embarking on their quest – their phasing can thwart boulder fort strategies employed against Master Kaen.

NPC xorns cannot cross the water in the castle level, but heroes polymorphed into xorns can – it is often enough to lure them across the drawbridge and raise it behind you if you are phasing or otherwise trying to avoid them. Xorns also cannot be destroyed by the drawbridge under normal circumstances due to their phasing; however, if there are two phasing monsters on both squares of the drawbridge (the portcullis and the moat in front), one of them will be killed if the drawbridge is raised.

Polyself

Due to their unusual abilities, xorns are one of the most useful monsters to polymorph into for various applications:

• Eating jewelry for intrinsics
• Phasing across difficult-to-navigate levels such as Asmodeus' Lair or the Stronghold of the Master Assassin - note that you cannot phase across the boundary between the two parts of Moloch's Sanctum, or anywhere on the Astral Plane
• Heading directly to the wand of wishing in the Castle during a speedrun or with a weak character

Xorns cannot wear body armor or cloaks, and morphing into a xorn will destroy them if you are wearing any, so be sure to remove these items before making the transformation. Remember that you can cross water while polymorphed into a xorn, although other xorns cannot.

If you return to normal form while phasing through a wall adjacent to open space, you will be able to move into it. However, if you return to normal form while phasing through the middle of solid stone with no adjacent space, you will be unable to move: you can teleport out, pray (since being stuck in a wall without having phasing is a major problem), or re-polymorph yourself into a xorn or earth elemental.

History

The xorn is introduced in Hack for PDP-11, a variant of Jay Fenlason's Hack.

In NetHack 3.4.3, xorns were subject to a few notable bugs:

• Xorns could be created in inaccessible areas, such as outside the Sokoban walls. This was bug C343-151.
• When a player polymorphed into a xorn returned to their normal form and was in open space, they would be stuck in a pit that doesn't exist; this was bug C343-17.

Origin

The xorn originally comes from Dungeons & Dragons, where it debuts in the 1st Edition Monster Manual of Advanced Dungeons & Dragons. Xorns come from the Elemental Plane of Earth and are depicted as odd and radially-symmetrical creatures: a large mouth sits at the top of their rocky body, surrounded by three long arms interspersed with their three eyes and three stumpy legs. All of their limbs are evenly spaced, and their arms end in sharp talons.

Like many creatures from their Elemental Plane, xorns can travel through ground and stone as if it were water; xorns encountered outside their home plane are not especially peaceful, but typically only attack anything that attacks them first or else impedes their hunting for the usual xorn diet of scavenged stone and minerals (including some types of metals). This may explain the unused message present in the code of NetHack for eating flint stones.

Variants

dNetHack

In dNetHack, the Elder Elemental Eye at any level of wards can protect against xorns.

SLASH'EM

In SLASH'EM, xorns hit as +2 weapons.

SlashTHEM

In SlashTHEM, xorns are additionally lithivorous and can eat stone in addition to metal.

Encyclopedia entry

A distant cousin of the earth elemental, the xorn has the
ability to shift the cells of its body around in such a way
that it becomes porous to inert material. This gives it the
ability to pass through any obstacle that might be between it
and its next meal.