When one of a character's primary attributes (strength, intelligence, or dexterity) is lowered to 0 or below, the character suffers crippling penalties until that attribute is restored and stays above 0 for a period of time equal to: 10 + 1d10 + the number of turns it was below 0 (Max: 200 turns).
The following can all drain your attributes:
- By 1 at a time:
- By more than 1 at a time:
- Malmutate and Corrupting Pulse can give permanent and transient mutations respectively, which can include reduced attributes.
- Brain Feed: this is really dangerous for players with low intelligence, as it can drain 1-3 in one go.
- Spell miscast effects, as caused by actual miscasts, Hell effects, and mummy death curses.
- Evoking certain items, such as a crystal ball of energy or the staff of Wucad Mu.
- Stepping on or being in view of a monster stepping on Zot traps.
As you gain experience, you regain stats lost through any of these means (except malmutate).
Stats can be more permanently lowered by the following means:
- Mutations which affect attributes (this lasts until the mutation is removed somehow).
- Equipment with negative stat modifiers (but you can remove the equipment to restore the stat).
- Jiyva's stat shuffling. (will never reduce a stat to zero)
The last two never lower a base stat to zero. Sustain attributes provides no help with any of these, and the stat does not restore naturally.
The following effects occur when any stat reaches 0:
- you immediately suffer 2-4 turns of paralysis which ignores a Formicid's stasis
- you are slowed until the stat completely recovers. (doesn't stack)
The following effects are dependent on the specific stat which was drained to 0:
- Your HP regeneration rate is divided by 4
- Your EV score is set to 2 + size_bonus + Repulsion field bonus
- Your SH score is set to 0
- Your stealth score is set to 0
- You can't stab monsters
Any character with a particularly low attribute should be aware of the dangers involved. Any attribute below 5 could conceivably be reduced to 0 by a single unfortunate effect, and below 10 are vulnerable to stat zero from repeated effects.
- Cursed artefact equipment can reduce an attribute by up to 6 for as long as it's equipped, so be cautious about wearing unidentified items if you're at risk.
- Miscast effects, Hell effects, Zot traps, and mummy death curses can temporarily reduce an attribute by up to 4 in one go. You may wish to bring all of your attributes up to a minimum of 8 to guarantee that you can survive a single worst-case scenario shot from either one.
Prior to 0.17, taking further stat damage after a stat reached 0 would inflict HP damage.