Passive attack

In NetHack, some monsters possess a passive attack - it is used automatically in retaliation to a melee attack against the monster. They can be avoided by use of ranged weapons, pounding with a polearm or lance, or being resistant to the attack. Passive attacks are not affected by magic cancellation.

The most infamous example of such a passive attack is the floating eye's paralysis gaze - hitting a floating eye normally paralyses the player for a period of time, during which they are vulnerable to outside attack - a cause of numerous YASDs. Other well-known examples include the various jellies, puddings, molds and acid blobs.

A passive attack is denoted by AT_NONE in the source code.

List of passive attacks

Passive attacks against the player are handled in function passive. Monsters have at most 1 passive attack, which is defined separately from any other attacks they might have.

Acid

b acid blob, j spotted jelly, j ochre jelly, F green mold

• 50% chance of an acid damage. If this succeeds, there's a 1/30 chance that your armor is subject to corrosion
• 1/6 chance, independent of the above, that whatever you attacked with (boot, weapon, etc) is subject to erosion
• Your strength is abused

Stoning

c chickatrice, c cockatrice

• If you hit with a bare appendage, you turn to stone and die instantly (unless stoning resistant)

Rust

R rust monster

• If the monster is cancelled, nothing happens
• If you kicked it, your boots suffer the effects of a rust trap
• Otherwise, 1/6 chance that your weapon/gloves are subject to rust

Corrosion

P black pudding

• Exactly like the rust attack above, but with the more-powerful corrosion effect

Magic missile

@ Oracle (monster) (the source code comment is "wrath of gods for attacking Oracle")

• If you have magic resistance, no effect
• Else, you are hit with a magic missile attack

Drain enchantment

R disenchanter

• If the monster is canceled, nothing happens
• If you attacked with an enchanted weapon/boots/gloves, they lose 1 enchantment. Artifact weapons resist the drain 90% of the time, and ordinary equipment resists 10% of the time.

Paralysis

b gelatinous cube, e floating eye

• If the monster is canceled or dies from the blow, nothing happens
• If you have free action, "You momentarily stiffen"
• If it is a floating eye and you have reflection, you cannot see it, or it is blind, nothing happens
• Else, there is a 2/3 chance that you will be paralyzed
• Being frozen by a gelatinous cube abuses dexterity

Cold

j blue jelly, F brown mold

• If the monster is canceled or dies from the blow, or if you are cold resistant, nothing happens
• Else, there is a 2/3 chance that you suffer a cold attack
• The monster gains half its attack damage in HP, possibly increasing its max HP
• If the monster's max HP is now high enough, it reproduces

The self-healing makes blue jellies especially deadly to lower-level characters who can't reliably hit hard enough to offset the healing.

Stunning

F yellow mold

• If the monster is canceled or dies from the blow, nothing happens
• 2/3 chance that you become stunned

Fire

v fire vortex, E fire elemental, F red mold

• If the monster is canceled or dies from the blow, or if you are fire resistant nothing happens
• 2/3 chance of fire damage
• If you are polymorphed into an iron golem, you heal by the damage amount, instead

Electricity

v energy vortex

• If the monster is canceled or dies from the blow, or if you are shock resistant nothing happens
• 2/3 chance of shock damage
• If you are polymorphed into a flesh golem, you heal by 1/6 of the damage amount

Sticky

m large mimic, m giant mimic

• If you walk into the mimic without knowing that there is a monster there, you are affected by their sticking attack, and cannot move away.

Slime

• Although the green slime has a passive slime attack defined, there is no code to handle it.

References

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.