View source for Magic resistance (monster)

In ''[[NetHack]]'', monsters have some degree of innate '''magic resistance''', also known as '''monster MR'''. Monsters' magic resistance allows them to resist various attacks, generally of a "magical" nature. It is handled by the resist() function&mdash;if a monster successfully resists an attack, it takes roughly half damage.{{refsrc|src/zap.c|4802|nethack=3.6.0}} Players cannot ever gain monster-style resistance, e.g. through [[polymorph]], and must instead rely upon [[magic cancellation]] and [[magic resistance]].

Monster magic resistance is separate from the [[magic resistance]] property provided by various worn or carried [[item]]s, which some monsters such as [[gray dragon]]s and [[Angel]]s also have intrinsically; this form of "player-style" magic resistance does not affect [[taming]] and [[conflict]], but renders [[polymorph trap]]s ineffective. Neither type of magic resistance will protect monsters from level teleporters.

==Description==
MR is given as a number from 0 to 100. This is frequently given as a percentage, although this is not entirely accurate. The chance of a monster resisting is given as follows:

 Chance = MR/(100 + (attack level) - (defense level)){{refsrc|src/zap.c|4842|nethack=3.6.0}}

which is only equal to MR as a percentage when attack and defense level are equal. Zero MR monsters will never resist.

Attack level is calculated as follows, where the defense level is the [[monster level]] of the target, which has a maximum of 50:

{|class="prettytable"
! Source
! Attack level
|-
| [[spellcasting|spell]]
| Caster's level
|-
| [[wand]], [[polytrap]]{{refsrc|src/trap.c|2588|nethack=3.6.0}}
| 12
|-
| [[tool]]
| 10
|-
| [[weapon]]
| 10
|-
| [[scroll]]
| 9
|-
| [[potion]]
| 6
|-
| [[ring]]
| 5
|}

All this also determines the chance that monsters (including [[pet]]s resist conflict; conflict from the [[Sceptre of Might]] is treated the same as the [[ring of conflict]] for this purpose.

==List of effects subject to monster MR==
{{todo|A list of all effects subject to monster mr, and/or confirmation that all those effects mention they are subject to it and link here.}}

==Strategy==
Monster magic resistance generally determines what strategies are effective against certain monsters - for example, the [[Riders]] have complete monster magic resistance, but {{monsymlink|Pestilence}} and {{monsymlink|Famine}} can be subjected to [[level drain]], making it possible for magical effects to work on them if their level is drained enough; {{monsymlink|Death}} is completely resistant to drain life.

==Messages==
{{message|<[[Foo]]> resists!|A monster resisted an attack; this is shown only in some cases.}}

==Variants==
Some variants change the monster magic resistance stats for certain monsters that are included from vanilla ''NetHack'' or other variants, and may additionally change the name to further distinguish it from the magic resistance property.

===NetHack Fourk===
In [[NetHack Fourk]], the stat is referred to as '''willpower'''.

===FIQHack===
In [[FIQHack]], this stat is also called '''willpower''', with the attacker bonus from wands dependent on the [[Wands Balance Patch|wand skill]].

===xNetHack===
[[xNetHack]] calls this stat '''magic saving throw'''.

===EvilHack===
In [[EvilHack]], this stat is referred to as '''magic saving throw''' in the monster lookup; various monsters added from ''NetHack'' and other variants also have their magic saving throw improved.

==References==
<references/>
{{nethack-360}}
[[Category:Monster attributes]]