Corruption is the means by which the PC is tainted by the essence of Chaos. (S)he can be corrupted by being damaged by a creature of chaos, triggering a corruption trap, eating the corpse of a corrupted creature, or local background corruption. A large amount of corruption can also be gained by drinking a potion of raw chaos. Some powerful artifacts of chaos will corrupt the PC simply by being in his/her possession; equipping them will amplify the effect.

Each new corruption means that PC gains new abilities, most of them granting some kind of advantage in exchange for some disadvantage. Some of these abilities are quite powerful, but beware: if the PC becomes fully corrupted, (s)he will be transformed into a writhing mass of primal chaos, and the game will end.

PCs get one corruption for each 1000 corruption points (CP) they accrue. Any incoming corruption is adjusted by the following factors:

In version 1.2.0, 17 new corruptions were added — bringing the current total to 35. The amount required to corrupt the PC to death still remains at 18; this means that for each PC, it is only possible to get a subset of all possible corruptions. The chosen subset varies from character to character (regardless of race or class). Note that all of the new corruptions added were based partially or fully on suggestions made on the ADOM forums[1].

Additionally, in 1.2.0[2] the corruption system has additional effects for the PC: with a certain number of corruptions the PC will get bonuses to Strength, Dexterity, Toughness and Mana, and a penalty to Willpower, depending on alignment.
The gains or losses to such stats are as follows:

  • If chaotic: (amount of corruptions)/2 point(s)
  • If neutral, (amount of corruptions)/3 point(s)
  • If lawful, (amount of corruptions)/4 point(s)

Table of corruptionsEdit

Name Good side Bad side Keeper score Specific notes
Acid blood Acid immunity, blinds monsters who hit the PC in melee Blind monsters with teleporting ability will teleport every time they move, making them hard to track; this can make the final battle with Andor Drakon even more perilous. 5 Also does minor damage together with the blinding
Black eyes See invisible, +3 Pe None 4
Devour Order Eating corpses of lawful monsters gives a 1d100 speed boost None 4 Lawful corpses are somewhat hard to obtain/farm.
Gills Water breathing -3 Ap 4
Sulphuric breath Drakeling-like acid spit -4 Ch 4 Drakelings already have this
Antennae Sometimes reveals map close to the PC -4 Ap 3 As of 1.2.0, Appearance influences corruption rate; map reveals are too rare to have a significant influence
Bloody sweat +5 speed -2 Ch, -4 Ap 4 Rumored to increase the chance of the PC bleeding; if true, this makes it dangerous for low HP characters such as elven casters.
Bronze bones +3 PV -2 Dx, -2 DV 4 Extremely good early on; later on swapping DV for PV likely does not matter.
Chaos whisper +4 Le, +2 Ma -6 Wi 2 Reasonable trade-off if your character needs Learning; outside of the early-game, Willpower is more important.
Babbling mouth +8 Le, periodically acts like wand of wonder casts Stealth impossible, -6 Ch, -4 Pe, -6 Ap 2 Casts drain all PP so this is a must-remove for caster by mid game; might cause problems by casting attack spells on Dwarftown, Casino level monsters, etc. Learning boost might be beneficial for borderline casters to learn some spells.
Bulging cranium +6 Le, +4 Wi -3 To, -4 PV, -6 Ap 4(2) Good for spellcasters/mindcrafters, bad for melee characters
Stilts Decreases movement energy cost by 25% -4 PV, -6 Ap, reduces kick damage 5 4 PV in exchange for free blessed seven league boots (in dungeons) is a great trade. Somewhat weaker for characters who have movement cost reductions through class powers.
Scales +8 PV -6 Dx, -4 Ap 4 Extremely good early on, but still a fair trade later.
Thin and nimble +6 DV, reduced PC weight Increased hunger rate 5 Food for DV is an excellent trade. Helps with entering the Quickling Tree and climbing down the Rift.
Rage +6 melee damage -9 DV 2 Bad trade-off; might bypass y/n prompt when walking into peaceful monsters (dwarf, farmer)
Astral attunement Teleportitis Teleportitis 4(1) Depends on how you value teleportitis and whether you have teleport control
Extra eyes +6 Pe -6 Ap 3 As of 1.2.0, appearance is more important than perception by mid-game
Very light +4 Dx, +20 speed, reduced PC weight -6 St, -6 To, -6 Ap 4 Needs to be evaluated in each individual case. Some late game ultra-goers can probably opt for speed over Strength and Toughness (especially since Toughness has diminishing returns), but in a fast game the negatives are significant... but so are the positives. Helps with entering the Quickling tree and climbing down the Rift.
Horns +2 damage for melee attacks with weapon, +3 for unarmed combat -4 Ap 3 Not worth removing individually, but not really worth keeping either.
Hooves +8 kick damage -6 Dx 2 Bad trade-off, but Dexterity is not the most useful stat for most characters
Healing tissue Gives ~20hp per 100 turns Occasionally leaves permanent scars; -1 Dx, -1 Ap per scar (even after removing the corruption) 3(4) Good early on and if you play fast (for a game finished in the ~50k turn range healing likely outweighs scars).
Maggots +4 DV, spawns tame worms -6 To, -2 Ch, -4 Ap 1 Toughness is one of the most important stats, no real bonuses to compensate
Merged eyes +4 Pe (blocked by headgear) -2 Ap, -2 Ch, -1 melee to-hit, -4 ranged to-hit 2 Not worth removing individually, but not really worth keeping either.
Thorns Improves base unarmed damage from 1d3 to 3d3 -2 Dx, -3 Ap 2 Unarmed specialist monks and beastfighters get no benefit at all.
Mana battery Drains wands for more max PP, reduced spell cost Drains wands 1(3) Quite desirable for a PC aspiring to become an Archmage. It's extremely annoying for melee character as certain areas of game are lot of easier with a well-boozed wand of fireballs; casters might keep it, especially if they lack class powers reducing casting costs (necromancers, paladins).
Mists of ChAoS See invisible -10 Pe 2(3) Early on losing 10 perception might be hard to compensate, later on PC is likely to have a means of see invisible anyway
Cold blood Drakeling-like relation to cold, heat Drakeling-like relation to cold, heat, -10 speed, -2 Dx, -1 Ap 2 It's likely positive in the ToEF or the occasional red dragon vault (due to high speed gains), but base -10 speed makes it bad anywhere else
Unholy aura +6 DV -10 Ch, aura 2(4) Since the aura applies to non-hostiles, it depends on the game stage. If you are in the middle of Thrundarr's quests, this is horrible. Mid-game it might cause problems with shopkeepers, HMV, etc. If you are on the final dive towards the chaos gate, it's free DV, since charisma is mostly useless.
Tentacle mouth +6 Dx -15 Ap, casting/speaking failures 2(1) The only case it's good is if you are a melee fighter who has Appearance at 1 (likely some chaos knights), otherwise it's a nuisance to interact with NPCs and a huge Appearance penalty. Casters should remove it ASAP.
Poison hands Poisons monsters in melee Turns potions into poison, curses food 1(2) Effects are canceled while wearing thick gauntlets; high priority to remove if you do not have thick gauntlets. Even if you do, not worth keeping.
Hate the sun Periodically casts Darkness Periodically casts Darkness 2 By mid-late game it is more annoying than dangerous, but it does not provide any real benefit in the long run.
Apish look +3 St -1 Le, -1 Wi, -2 Ch, -3 Ap 3(1) Periodically kicks in, giving +1 St, To and -1 Le, Wi, Dx, Ch, Ap, which is accumulative and not removed with the corruption. If you are a caster this reduces Le and Wi which you need, if you are a melee fighter this gives +St and +To which is sweet. As of 1.2.0 this is the final corruption received, so it may be necessary to remove to avoid dying to corruption.
ChAoS hands None Corrupts monsters and heals corrupting monsters 1(3) If you are a primary caster this does not matter; rather bad for melee fighters, especially in areas like D:50.
Decay +10 Wi Halved HP regeneration, -5 St, -5 Ap, -10 speed 1 Casters (with good healing spells) might want to keep it in rare situations for the willpower bonus; highly undesirable due to speed and regeneration penalties otherwise.
Stiff muscles +2 St, +4 PV Increases the energy cost of all actions by 1.5x 1 Any action you take is 1.5 times slower. Remove ASAP.

Score explanation:

  1. always remove ASAP;
  2. remove, unless there are reasons to keep it;
  3. neutralish;
  4. keep, unless there are reasons to remove it;
  5. always keep.