Acid is a damage type most commonly dealt by jelly and yellow draconians, which can be resisted with resist corrosion. It no longer corrodes your equipment, but instead applies temporary corrosion status, which lowers your AC and slaying.
Sources of Acid
Acidic damage can come from several sources.
Some monsters have acidic flesh:
The following monsters can spit acid:
The above damage bypasses AC and may add corrosion status.
Acidic Melee Attacks
The following monsters have acidic melee attacks:
Worshipers of Jiyva are unaffected by slime walls.
Corrosion resistance reduces damage taken from acid and reduces the chance of being further corroded.
The sources of Corrosion resistance are:
- being a yellow draconian
- Ring of resist corrosion
- Tiamat's dragonskin cloak (50% chance per attack)
- Having the yellow scales mutation at level 3
Players with corrosion resistance take 50% damage from acid. All monsters with any degree of acid resistance are completely immune to acid damage.
Corrosion is a temporary status effect which gives a stackable -4 to slaying and AC for as long as it lasts. Corrosion will be repaired after enough turns have passed. It can also be removed with Potion of cancellation or Purple Draconian's breath aimed at yourself.
Prior to 0.15, corrosion instead caused permanent damage to weapons and armor, reducing their enchantment values, possibly into the negatives. Also, potions of resistance did not grant rAcid or rCorr. There were previously three tiers of acid resistance, each one further reducing acid damage; now there is only one level which is merged with corrosion resistance.