# Helm
Helms are one of the seven slots for armor. Their primary use is protecting your head and cranium, especially against mind flayers. The most popular helms to carry are helm of telepathy, helm of brilliance, and elven leather helm. Cornuthaums are occasionally used by wizards, and a helm of opposite alignment is often used on the ascension run.
The helm of telepathy grants extrinsic telepathy, similar to an amulet of ESP. The helm of brilliance will increase your intelligence and wisdom by its enchantment, so +5 HoB and 18 Int and 17 Wis will produce 23 Int and 22 Wis. Elven leather helms can take a higher enchantment than other items and weigh less than most other helms: 3 wt versus 50.

The following information pertains to an upcoming version (NetHack 3.7.0). If this version is now released, please verify that it is still accurate, then update the page to incorporate this information.

The helm of brilliance now has a fixed unidentified description of "crystal helm", and is made of glass so does not inhibit spellcasting. A new helm has been added, the helm of caution, which conveys warning when worn.
Contents

1 List of helms
2 Hard helms
3 Variants
4 References

List of helms

Name

Cost

Weight

AC

Material

Appearance

Effect

Fedora

1

3

0

Cloth

Dunce cap

1

4

0

Cloth

Conical hat

Autocurses when worn; Int and Wis set to 6

Cornuthaum

80

4

0

Cloth

Conical hat

MC1; wizards can enchant to +7; clairvoyance and Ch+1 for wizards; blocks clairvoyance and Ch−1 for non-wizards

Elven leather helm

8

3

1

Leather

Leather hat

Can be enchanted to +7

Orcish helm

10

30

1

Iron

Iron skull cap

Dented pot

8

10

1

Iron

Dwarvish iron helm

20

40

2

Iron

Hard hat

Helmet (kabuto)

10

30

1

Iron

(randomized)

Helm of brilliance

50

50

1

Iron

(randomized)

Int and Wis +/− enchantment amount; doesn't hinder spellcasting

Helm of opposite alignment

50

50

1

Iron

(randomized)

Autocurses when worn; opposite alignment

Helm of telepathy

50

50

1

Iron

(randomized)

Grants telepathy

The helms marked (randomized) in the chart above have their appearances randomly chosen from:

   plumed    etched    crested    visored

Of these, the visored helmet is always special. It protects against the blinding attack of ravens and the venom-spitting attack of cobras.

Hard helms
Helms made of metal provide protection against falling objects, greatly reducing the damage taken from falling rock traps, iron balls, non-blessed scrolls of earth, and objects you throw upward. The helm of brilliance is the only item providing this benefit without increasing spell failure rates.
Polymorphed players or monsters with horns,[1] such as ki-rin or unicorns, cannot equip[2] or wear[3] metal helms. When you polymorph into a horned monster while wearing a soft helm, you receive the message "Your horn(s) pierce(s) through your 

<hat>." This does not damage or destroy your helm, though a comment in the source suggests that it someday might.[4] There is no special message for putting on a soft helm over horns.

Variants
In UnNetHack and SporkHack, a helm with the appearance tin foil hat blocks telepathy from all sources.

References

↑ num_horns in mondata.h

↑ do_wear.c in NetHack 3.4.3, line 1293

↑ polyself.c in NetHack 3.4.3, line 624

↑ polyself.c in NetHack 3.4.3, line 629

This page may need to be updated for the current version of NetHack.
It may contain text specific to NetHack 3.4.3. Information on this page may be out of date.
Editors: After reviewing this page and making necessary edits, please change the {{nethack-343}} tag to the current version's tag or {{noversion}} as appropriate.

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