Experience level

Your experience level in NetHack is a measure of the overall power of your hero and progress of your adventure. The more experienced you are, the better you become at both fighting and magic.

Experience points (XP) are the units that you accumulate to increase your level. Depending on the showexp option, you may see a display of your XP or only see your current experience level.

You start at level 1 and can reach a maximum level of 30. Monsters also have an experience level defined, but it can only be seen with a wand of probing, stethoscope, or Magicbane. These will also show your own level unless you are polymorphed. In that case, you could work backward from spell failure rates.

Effects

Gaining an experience level will have a number of effects on gameplay:

• Increases your maximum hit points
• Increases your maximum energy
• Increases your skill slots by one
• Increases your chance to hit in combat
• Increases your chance of successfully learning a spell from spellbook
• Decreases your spell failure rate
• Increases damage done by certain spells (e.g., magic missile)
• Increases difficulty of monsters generated
• Changes your rank, based on your role (and possibly gender)
• Characters at level 12 or more can teleport at will if they have teleportitis
• Characters at level 14 or more can attempt the Quest
• Increases your chance of converting an altar
• Increases your chance of successfully playing certain musical instruments
• Scrolls will have more meaningful error messages once you aren't considered a beginner anymore ("You have a strange feeling, then it passes.")

Experience level has no direct effect on your attributes.

Gaining levels

There are several ways to gain an experience level, ranging from obvious to somewhat obscure:

• Experience points (mostly from killing monsters).
• Quaffing a blessed or uncursed potion of gain level.
• Eating a wraith corpse.
• Chance from incubus or succubus encounter.
• Chance when polymorphing into your own race.
• Chance of regaining a lost level when praying successfully at a coaligned altar.
• Regaining a lost level when quaffing a potion of full healing. Up to half of your lost levels can be regained this way.

You may never gain more than one experience level at a time; killing a water demon at XP1:0 will only put you on 2:39, not 4:169 as might be expected. (You can, however, gain multiple experience levels in a single turn, as for example when a beginner character manages to destroy many creatures at once with an exploding gas spore.)

If you are already at level 30, experience points will not raise your level. Except for polymorph, the "Gain level" methods above will cause your maximum HP and energy to increase.

Losing levels

It's also possible to lose your hard-earned experience levels:

• Level drain attacks
  • Monster attacks--vampire bite, wraith touch, or Demogorgon sting
  • Getting hit by the Staff of Aesculapius or Stormbringer
  • Getting zapped with the spell of drain life (or the wand of draining in SLASH'EM)
• Chance from foocubus encounter
• Chance when receiving a god's anger from incorrect prayer or sacrifice
• Chance when polymorphing into your own race

Drain resistance protects against all these except polymorph. If you kill anything after losing an experience level you immediately gain it back, but only one level can be restored in this way. A blessed potion of full healing will also restore a lost level, but only up to half of those lost. For this reason care should be taken when fighting wraiths.

When losing a level, your HP and maximum HP are both decreased by the same amount you would have gained by gaining a level, down to a minimum of one. Energy and maximum energy work similarly, down to a minimum of zero. You will be just one experience point away from regaining the lost level. Being drained below experience level one is deadly, although an amulet of life saving can rescue you, leaving you at level one with no experience.

There are several uses for intentionally lowering your level; these are typically referred to as "drain for gain".

Experience points required per level

Level	NetHack - XP required	SLASH'EM - XP required	dNethack - XP required
1	0	0	0
2	20	40	20
3	40	80	50
4	80	160	100
5	160	320	200
6	320	640	400
7	640	1280	800
8	1280	2560	1600
9	2560	5120	3200
10	10000	10000	6400
11	20000	20000	10000
12	40000	40000	14000
13	80000	80000	19000
14	160000	150000	25000
15	320000	250000	32000
16	640000	300000	41000
17	1280000	350000	52000
18	2560000	400000	65000
19	5120000	450000	80000
20	20000000	500000	97000
21	40000000	550000	117000
22	80000000	600000	140000
23	160000000	650000	166000
24	320000000	700000	195000
25	640000000	750000	227000
26	1280000000	800000	263000
27	2560000000	850000	303000
28	5120000000	900000	347000
29	10240000000	950000	395000
30	20480000000	1000000	450000

The following graphs show the amount of XP required for each level. These should clearly illustrate the significant difference between the leveling curve in SLASH'EM and NetHack.

Messages

Welcome to experience level <x>.

You have gained a level.

Aloha level <x>.

You have lost a level as a Tourist.

Sayonara level <x>.

You have lost a level as a Samurai.

Farvel level <x>.

You have lost a level as a Valkyrie.

Fare thee well level <x>.

You have lost a level as a Knight.

Punardarsanaya level <x>.

(in UnNetHack) You have lost a level as a Monk.

Goodbye level <x>.

You have lost a level as any other role.

Monsters

Monsters also have experience levels, but they are largely a function of their maximum hit points. When a monster (usually a pet) kills a monster, it gains a few maximum hit points. As opposed to players, it does not gain current hit points from the maxHP increase. See also growing up.

SLASH'EM

Using draw blood to make a potion of vampire blood drains an experience level, and you are put at the minimum experience for the new level. Killing a wimpy monster won't get the level back.

As opposed to vanilla, in SLASH'EM a character will usually gain enough experience to reach XL30 naturally without pudding farming or other degenerate means. This advantage is slightly balanced by the higher experience requirement at low levels; thus most early characters will be about one level lower than their vanilla counterparts.

External links

• HP and power starting values, level increases, and regeneration in NetHack 3.4.3

This page is based on a spoiler by Dylan O'Donnell. The original license is:

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