Symset

Starting in NetHack 3.6.0, the symset option selects one of several symbol sets for display of a text-mode map for the normal dungeon. The roguesymset option does the same for the Rogue level. The file "symbols", placed in the directory where NetHack is installed, defines the available symbol sets. The user may edit this file to change existing symbol sets or to define new symbol sets.

The symset option supersedes IBMgraphics, DECgraphics and MACgraphics. Those options are still recognized for backward compatibility. It also replaces the variables named under Custom map symbols (3.4.3), except that BOULDER and WARNINGS are still accepted.

Individual symbols may be set in the options file with SYMBOLS:

SYMBOLS=S_boulder:0
SYMBOLS=S_golem:7
SYMBOLS=S_ghost:8

Available symbol sets

Normal dungeon

The following symbol sets are available for the normal dungeon and for the Rogue level:

• plain -- same as default, except that corners are +.
• Blank -- all symbols are blank spaces.
• IBMgraphics
• IBMGraphics_1 -- displays walls as solid lines and all other characters the same way as ASCII
• IBMGraphics_2 -- rolls back certain symbols to ASCII, for consistent display with code pages other than 437. The IBMgraphics article discusses code pages at length.
• curses -- similar to DECgraphics, adapted for the Curses interface
• DECgraphics
• MACgraphics -- for classic Mac. This port is currently (18 Jun 2026) broken. Modern Macs use the Unix port and can set one of the other options.
• Enhanced1 -- uses Unicode.
• Enhanced2 -- uses more Unicode symbols.
• AmigaFont -- assumes the font bundled with the Amiga port.

Rogue level

In addition to the above symbol sets, the following symbol sets are available for the Rogue level:

• RogueIBM
• RogueEpyx
• RogueWindows

Of these, only RogueEpyx displays in color. RogueIBM and RogueWindows differ only in that RogueWindows specifies ε for engravings in a room (S_engroom).

The symbols file supports limiting a symbol set to the main dungeon, but no preconfigured symbol set is restricted this way.

File format

The symbols file is a plain text file and can be edited by the user. Blank lines are ignored. Comments begin with '#' and continue to the end of the line. Lines consist of either the keyword "finish" standing alone or a keyword, a colon or equals sign, and a value. Keywords are not case sensitive.

A symbol set consists of:

• a single line with keyword "start" or "begin" and a value constituting the name of the symbol set
• a single line with keyword "handling" and a value of, "DEC", "IBM", "CURS", "MAC" or "UTF8"
• an optional single line with keyword "description" and a line to be displayed in the options menu, to describe the symbol set
• an optional single line with keyword "color" or "colour" and a value of any of "true", "yes", "on", "false", "no" or "off"; the default is to enable color in the main dungeon and disable it in the Rogue level
• an optional single line with keyword "restrictions" and a value of "primary" or "rogue"; the default is no restriction
• zero or more lines in which the keyword is a symbol name and the value is the character to be displayed; symbols for which no line is defined will be displayed as ASCII
• a single line with keyword "finish" and no value

The character may be a single printable character other than backslash (which begins an escape), caret (which indicates a control character; you probably don't want this) or '#' (which begins a comment), or it may be an escape sequence. C-style escape sequences of the form '\123' are interpreted as octal, '\x45' as hex and '\d123' as decimal. '\Mx' gives a "meta" character, with the eighth bit set.

Recognized symbol names are as follows:

Default (ASCII)	Name	Description
Walls, doors etc.
-	S_blcorn	bottom left corner (of a room)
-	S_brcorn	bottom right corner (of a room)
-	S_crwall	cross wall
-	S_hwall	horizontal wall
-	S_tdwall	wall
-	S_tlcorn	top left corner (of a room)
|	S_tlwall	wall
-	S_trcorn	top right corner (of a room)
|	S_trwall	wall
-	S_tuwall	wall
|	S_vwall	vertical wall
#	S_corr	corridor
#	S_litcorr	lit corridor
#	S_engrcorr	engraving in a corridor
	S_stone	solid rock
.	S_ice	ice
.	S_room	floor of a room
.	S_darkroom	dark part of a room
`	S_engroom	engraving in a room
.	S_ndoor	doorway (with no or broken door)
+	S_hcdoor	closed door (in horizontal wall)
|	S_hodoor	open door (in horizontal wall)
+	S_vcdoor	closed door (in vertical wall)
-	S_vodoor	open door (in vertical wall)
>	S_dnladder	ladder down
>	S_dnstair	staircase down
<	S_upladder	ladder up
<	S_upstair	staircase up
>	S_brdnladder	branch ladder down
>	S_brdnstair	branch staircase down
<	S_brupladder	branch ladder up
<	S_brupstair	branch staircase up
Dungeon features
	S_air	air
_	S_altar	altar
#	S_bars	iron bars
#	S_cloud	cloud
{	S_fountain	fountain
|	S_grave	grave
#	S_hcdbridge	horizontal raised drawbridge
.	S_hodbridge	horizontal lowered drawbridge
#	S_vcdbridge	vertical raised drawbridge
.	S_vodbridge	vertical lowered drawbridge
}	S_lava	molten lava
}	S_lavawall	wall of lava
#	S_poisoncloud	poison cloud
$	S_goodpos	valid position
{	S_sink	sink
\	S_throne	opulent throne
#	S_tree	tree
}	S_pool	water
}	S_water	water
Traps
^	S_anti_magic_trap	anti-magic field
^	S_arrow_trap	arrow trap
^	S_bear_trap	bear trap
^	S_dart_trap	dart trap
^	S_falling_rock_trap	falling rock trap
^	S_fire_trap	fire trap
^	S_hole	hole
^	S_land_mine	land mine
^	S_level_teleporter	level teleporter
^	S_magic_portal	magic portal
^	S_magic_trap	magic trap
^	S_pit	pit
^	S_polymorph_trap	polymorph trap
^	S_rolling_boulder_trap	rolling boulder trap
^	S_rust_trap	rust trap
^	S_sleeping_gas_trap	sleeping gas trap
^	S_spiked_pit	spiked pit
^	S_squeaky_board	squeaky board
^	S_statue_trap	statue trap
^	S_teleportation_trap	teleportation trap
^	S_trap_door	trap door
~	S_vibrating_square	vibrating square
^	S_trapped_door	trapped door
^	S_trapped_chest	trapped chest
"	S_web	web
Items
"	S_amulet	amulet
[	S_armor or S_armour	suit or piece of armor
0	S_ball	iron ball
+	S_book	spellbook
`	S_boulder	boulder
_	S_chain	iron chain
$	S_coin	pile of coins
%	S_food	piece of food
*	S_gem	gem or rock
!	S_potion	potion
=	S_ring	ring
`	S_rock	boulder or statue
?	S_scroll	scroll
(	S_tool	(useful item (pick-axe, key, lamp...)
/	S_wand	wand
)	S_weapon	weapon
.	S_venom	splash of venom
Monsters
<space>	S_ghost	ghost
A	S_angel	angelic being
B	S_bat	bat or bird
C	S_centaur	centaur
D	S_dragon	dragon
E	S_elemental	elemental
F	S_fungus	fungus or mold
G	S_gnome	gnome
H	S_giant	giant humanoid
J	S_jabberwock	jabberwock
K	S_kop	Keystone Kop
L	S_lich	lich
M	S_mummy	mummy
N	S_naga	naga
O	S_ogre	ogre
P	S_pudding	pudding or ooze
Q	S_quantmech	quantum mechanic
R	S_rustmonst	rust monster or disenchanter
S	S_snake	snake
T	S_troll	troll
U	S_umber	umber hulk
V	S_vampire	vampire
W	S_wraith	wraith
X	S_xorn	xorn
Y	S_yeti	apelike creature
Z	S_zombie	zombie
a	S_ant	ant or other insect
b	S_blob	blob
c	S_cockatrice	cockatrice
d	S_dog	dog or other canine
e	S_eye	eye or sphere
f	S_feline	cat or other feline
g	S_gremlin	gremlin
h	S_humanoid	humanoid
i	S_imp	imp or minor demon
j	S_jelly	jelly
k	S_kobold	kobold
l	S_leprechaun	leprechaun
m	S_mimic	mimic
]	S_mimic_def	mimic
n	S_nymph	nymph
o	S_orc	orc
p	S_piercer	piercer
q	S_quadruped	quadruped
r	S_rodent	rodent
s	S_spider	arachnid or centipede
t	S_trapper	trapper or lurker above
u	S_unicorn	unicorn or horse
v	S_vortex	vortex
w	S_worm	worm
~	S_worm_tail	long worm tail
x	S_xan	xan or other mythical/fantastic insect
y	S_light	light
z	S_zruty	zruty
&	S_demon	major demon
'	S_golem	golem
:	S_lizard	lizard
;	S_eel	sea monster
@	S_human	human or elf
Effects
)	S_boomleft	boomerang open left
(	S_boomright	boomerang open right
*	S_digbeam	dig beam
/	S_expl_tl	explosion top left
-	S_expl_tc	explosion top center
\	S_expl_tr	explosion top right
|	S_expl_ml	explosion middle left
	S_expl_mc	explosion middle center
|	S_expl_mr	explosion middle right
\	S_expl_bl	explosion bottom left
-	S_expl_bc	explosion bottom center
/	S_expl_br	explosion bottom right
!	S_flashbeam	flash beam
0	S_ss1	magic shield 1 of 4
#	S_ss2	magic shield 2 of 4
@	S_ss3	magic shield 3 of 4
*	S_ss4	magic shield 4 of 4
-	S_sw_bc	swallow bottom center
\	S_sw_bl	swallow bottom left
/	S_sw_br	swallow bottom right
|	S_sw_ml	swallow middle left
|	S_sw_mr	swallow middle right
-	S_sw_tc	swallow top center
/	S_sw_tl	swallow top left
\	S_sw_tr	swallow top right
-	S_hbeam	horizontal beam
|	S_vbeam	vertical beam
/	S_rslant	diagonal beam (NE/SW)
\	S_lslant	diagonal beam (NW/SE)

Glyph names

Glyph names begin with G_. These refer to individual things associated with a symbol, such as specific glyphs for monsters. S_angel, for example, covers all glyphs for monsters of the A class, but G_detected_female_archon is specifically a female Archon perceived via monster detection.

There are far too many possible glyphs to list them in any article of reasonable length. For Unix ports, including modern Mac, one can run ./nethack --dumpglyphids to get a complete list. This option does not work with all ports.

Example

The following defines the traditional IBMgraphics symbol set:

start: IBMgraphics
        Description: special line-drawing characters used for walls
#       Restrictions: primary
        Handling: IBM
        S_vwall: \xb3                   # meta-3, vertical rule
        S_hwall: \xc4                   # meta-D, horizontal rule
        S_tlcorn: \xda                  # meta-Z, top left corner
        S_trcorn: \xbf                  # meta-?, top right corner
        S_blcorn: \xc0                  # meta-@, bottom left
        S_brcorn: \xd9                  # meta-Y, bottom right
        S_crwall: \xc5                  # meta-E, cross
        S_tuwall: \xc1                  # meta-A, T up
        S_tdwall: \xc2                  # meta-B, T down
        S_tlwall: \xb4                  # meta-4, T left
        S_trwall: \xc3                  # meta-C, T right
        S_ndoor: \xfa                   # meta-z, centered dot
        S_vodoor: \xfe                  # meta-~, small centered square
        S_hodoor: \xfe                  # meta-~, small centered square
        S_engroom: \xee                 # epsilon
        S_bars: \xf0                    # equivalence symbol
        S_tree: \xf1                    # plus or minus symbol
        S_room: \xfa                    # meta-z, centered dot
        S_corr: \xb0                    # meta-0, light shading
        S_litcorr: \xb1                 # meta-1, medium shading
        S_engrcorr: \xb0                # meta-0, light shading
        S_fountain: \xf4                # meta-t, integral top half
        S_sink: \xf4                    # meta-t, integral top half
        S_pool: \xf7                    # meta-w, approx. equals
        S_ice: \xfa                     # meta-z, centered dot
        S_lava: \xf7                    # meta-w, approx. equals
        S_lavawall: \xf7                # meta-w, approx. equals
        S_vodbridge: \xfa               # meta-z, centered dot
        S_hodbridge: \xfa               # meta-z, centered dot
        S_water: \xf7                   # meta-w, approx. equals
        S_vbeam: \xb3                   # meta-3, vertical rule
        S_hbeam: \xc4                   # meta-D, horizontal rule
        S_sw_ml: \xb3                   # meta-3, vertical rule
        S_sw_mr: \xb3                   # meta-3, vertical rule
        S_expl_ml: \xb3                 # meta-3, vertical rule
        S_expl_mr: \xb3                 # meta-3, vertical rule
        G_vwall_sokoban:  /blue
        G_hwall_sokoban:  /blue
        G_tlcorn_sokoban: /blue
        G_trcorn_sokoban: /blue
        G_blcorn_sokoban: /blue
        G_brcorn_sokoban: /blue
        G_crwall_sokoban: /blue
        G_tuwall_sokoban: /blue
        G_tdwall_sokoban: /blue
        G_tlwall_sokoban: /blue
        G_trwall_sokoban: /blue
        G_vwall_gehennom:  /red
        G_hwall_gehennom:  /red
        G_tlcorn_gehennom: /red
        G_trcorn_gehennom: /red
        G_blcorn_gehennom: /red
        G_brcorn_gehennom: /red
        G_crwall_gehennom: /red
        G_tuwall_gehennom: /red
        G_tdwall_gehennom: /red
        G_tlwall_gehennom: /red
        G_trwall_gehennom: /red
        G_vwall_knox: /yellow
        G_hwall_knox: /yellow
        G_tlcorn_knox: /yellow
        G_trcorn_knox: /yellow
        G_blcorn_knox: /yellow
        G_brcorn_knox: /yellow
        G_crwall_knox: /yellow
        G_tuwall_knox: /yellow
        G_tdwall_knox: /yellow
        G_tlwall_knox: /yellow
        G_trwall_knox: /yellow
        G_vwall_mines: /brown
        G_hwall_mines: /brown
        G_tlcorn_mines: /brown
        G_trcorn_mines: /brown
        G_blcorn_mines: /brown
        G_brcorn_mines: /brown
        G_crwall_mines: /brown
        G_tuwall_mines: /brown
        G_tdwall_mines: /brown
        G_tlwall_mines: /brown
        G_trwall_mines: /brown
finish

Screenshots

Main dungeon

Here are four screenshots of the same scene, using the three IBMgraphics variants and also DECgraphics.

These screenshots are from NetHack 3.6.0. Some symbols may be different from NetHack 5.0.0.

With IBMgraphics

Note that the floor symbol is centered with respect to the @ sign on the left.

With IBMgraphics_2

The moat, the floor and the fountain are displayed with their ASCII symbols. The floor is an ASCII period, and displays low with respect to the @ sign on the left.

With IBMgraphics_1

The doors are displayed with their ASCII symbols.

With DECgraphics

Rogue level

Here are two screenshots of the same scene, using the two Rogue level symbol sets.

With RogueIBM/RogueWindows

With RogueEpyx