The (Not Yet) Comprehensive ToME 2.2.x Skill Spoiler

[Last modified 2007-09-30. See below for recent changes.]

It's a common dilemma among ToME players: which skills to raise? Well, that depends on the answer to the next question: What benefits am I getting from these skills? For some skills, like Magic, the effect of a skill increase is immediate and obvious (more mana, in this case), but some skills don't have obvious effects, leading one to wonder whether increasing, say, one's Weaponmastery skill is actually buying one anything.

This spoiler is an attempt to answer those questions. I've examined the source (specifically, the 2.2.0 thru 2.2.7 release versions) looking for everywhere a skill level is used, and I describe here the specific, quantitative effects that different skills have on gameplay.

[NOTE: This spoiler is (intended to be) correct for ToME v2.2.0 thru v2.2.7. There have been some changes since the previous version, v2.1.2; for information on that version, see the 2.1.2 version of this spoiler. For later versions of ToME, see the 2.3.x version of this spoiler.

Table of Contents

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Notation

For notational convenience, we will use the following conventions herein:

Skills vs. Abilities

As a result of ToME's Angband heritage, ToME characters have other skill-like properties that are not directly adjusted on the skill selection screen. These are listed on the 'C'haracter screen as "(Miscellaneous Abilities)", and include things like Fighting, Perception, and Saving Throw. [These are distinct, by the way, from the abilities listed on the "ToME Abilities Screen" under the 'N' command --- an unfortunate naming collision.] The base level of an ability is determined by your race, sub-race and class, and does not increase with level; some of them, however, increase along with the corresponding skill.

The amount by which a skill affects an ability depends on class, and is referred to as the "class modifier" for the ability, hereinafter denoted CM. The class modifiers for different abilities and classes are listed below. Typically, an ability will be increased by your scaled skill level in the corresponding skill, where the scale factor will be some multiple of the class modifier.

The skills

Some skills have additional annotations, as follows:

Combat (FF)

The Combat skill has the following effects:

Melee styles: Some subskills of Combat correspond to melee styles:

Weaponmastery (FF) [Combat@0.5]

The effects of the Weaponmastery skill are described in the "Melee styles" entry under Combat.

Submasteries: If all of your wielded melee weapons are covered by the same sub-skill of the Weaponmastery skill (as described below), you receive additional bonuses based on your skill level in said sub-skill:

  • You receive S/25 extra melee attacks.
  • You receive a to-hit bonus of +S and a damage bonus of +S/2 for melee attacks.
Sword-mastery [Weaponmastery@0.25,Combat@0.07]

Sword-mastery covers the following weapons:

  • Broken Dagger
  • Broken Sword
  • Dagger
  • Main Gauche
  • Rapier
  • Small Sword
  • Basillard
  • Short Sword
  • Sabre
  • Cutlass
  • Khopesh
  • Tulwar
  • Broad Sword
  • Long Sword
  • Scimitar
  • Katana
  • Bastard Sword
  • Great Scimitar
  • Claymore
  • Espadon
  • Two-Handed Sword
  • Flamberge
  • Executioner's Sword
  • Zweihander
  • Blade of Chaos
  • Bluesteel Blade
  • Shadow Blade
  • Dark Sword
  • Demonblade
  • Necromantic Teeth (see notes under Necromancy)

Its effects are described in the "Submasteries" entry under Weaponmastery.

Critical-hits [Sword-mastery@0.05]

If you are wielding a weapon covered by the Sword-mastery skill that weighs less than 5 pounds, your probability of scoring a critical hit with that weapon is increased by (S@2000) in 5000. In addition, the power of the critical hit is computed as though the weapon's weight were (S@400)//10 pounds greater.

Axe-mastery [Weaponmastery@0.25,Combat@0.07]

Axe-mastery covers the following weapons:

  • Hatchet
  • Cleaver
  • Light War Axe
  • Broad Axe
  • Great Axe
  • Slaughter Axe

Its effects are described in the "Submasteries" entry under Weaponmastery.

Hafted-mastery [Weaponmastery@0.25,Combat@0.07]

Hafted-mastery covers the following weapons:

  • Club
  • Whip
  • Quarterstaff
  • Mace
  • Ball-and-Chain
  • War Hammer
  • Lucerne Hammer
  • Three Piece Rod
  • Morning Star
  • Flail
  • Lead-Filled Mace
  • Two-Handed Flail
  • Great Hammer
  • Mace of Disruption
  • Mighty Hammer (of Grond, presumably)

Its effects are described in the "Submasteries" entry under Weaponmastery.

Stunning-blows [Hafted-mastery@0.05]

If you are wielding a weapon covered by the Hafted-mastery skill that weighs more than 5 pounds and you score a critical hit with that weapon, the monster will be stunned with probability S percent. If the monster is not currenly stunned, the stunning will last (S@60)+20 game turns (where 10 game turns corresponds to one player turn at normal speed); if it is already stunned, the stunning duration is increased by (S@30)+10 game turns, to a maximum of 200 game turns.

Polearm-mastery [Weaponmastery@0.25,Combat@0.07]

Polearm-mastery covers the following weapons:

  • Spear
  • Sickle
  • Awl-Pike
  • Trident
  • Fauchard
  • Broad Spear
  • Pike
  • Glaive
  • Halberd
  • Guisarme
  • Scythe
  • Lance
  • Trifurcate Spear
  • Heavy Lance
  • Scythe of Slicing
  • Beaked Axe
  • Battle Axe
  • Lochaber Axe

Its effects are described in the "Submasteries" entry under Weaponmastery.

Archery (FF) [Combat@0.5]

For notational convenience, we will use the technically ungrammatical singular "an ammo" in the following to refer to a single launched arrow, bolt or shot.

  • Your Bows/Throw ability is increased by (CM×7×S)/100.
  • Your probability of scoring a critical hit with a ranged attack is increased by (S@100)//50 percent.
  • The probability of an ammo breaking when thrown at a monster, normally 50 percent for arrows and 25 percent for shots and bolts, is divided by (S@10), rounded down to the nearest percent; thus, at skill level 50, arrows break with probability 5 percent, and bolts break with probability 2 percent. This does not apply to boomerangs, which have a constant 1-percent breakage chance.
  • A piercing shot will pass through a hit monster with probability S+45 percent, unless it has already done so the maximum number of times, as determined by the Combat skill above.
  • If you have the Ammo creation ability, the types of ammo that can be forged via the "Forge ammo" command under the 'm' menu depend on S:
    • If S≥1, you can forge shots from rubble. [We will describe the process for doing so here, since it is different from that of forging shots and bolts, and this difference has apparently confused many people (including, at one time, the author): First stand next to the pile of rubble; then select the "Forge ammo" skill under the 'm' menu , select "[S]hots", and indicate the direction to the pile of rubble when prompted.]
    • If S≥10, you can forge arrows out of junk in your inventory or at your feet ("junk" here means things like Broken sticks and Elf skeletons -- but not skeletons dropped by killed monsters).
    • If S≥20, you can forge bolts out of junk in your inventory or at your feet.

Submasteries: You can also gain additional effects depending on your skill level in the sub-skill of Archery corresponding to your wielded launcher (as described below):

  • You receive a to-hit bonus of +(S@25) for ranged attacks.
  • You receive a bonus to shots (as per a launcher of Extra Shots) of S/16. Not applied to boomerangs.
  • You receive a bonus to multiplier (as per a launcher of Extra Might) of S/25, with an additional +1 bonus if S≥30 and you have the corresponding ammo in your quiver. Not applied to boomerangs.
  • If S≥26, you can activate the "Fire piercing shots" option under the 'm' menu, which will cause a thrown ammo to pass through a hit monster with some probability; see also notes under Combat and Archery. [Actually, you can activate piercing shots as soon as S>0; it just doesn't have any effect until S≥26. -ed]
Sling-mastery [Archery@0.25,Combat@0.07]

Sling-mastery covers pebbles and iron/mithril shots launched by slings. Its effects are described in the "Submasteries" entry under Archery.

Bow-mastery [Archery@0.25,Combat@0.07]

Bow-mastery covers arrows launched by bows. Its effects are described in the "Submasteries" entry under Archery.

Crossbow-mastery [Archery@0.25,Combat@0.07]

Crossbow-mastery covers bolts launched by crossbows. Its effects are described in the "Submasteries" entry under Archery.

Boomerang-mastery [Archery@0.25,Combat@0.07]

Boomerang-mastery covers boomerangs thrown from the launcher slot. In addition to the effects described in the "Submasteries" entry under Archery, you also gain an addition +S/3 to-hit bonus when throwing a boomerang.

Barehand-combat (FF) [Combat@0.5]

In addition to the effects described in the "Melee styles" entry under Combat, the following effects are applied if you have selected the "Barehanded combat" melee style under the 'm' menu:

  • If you are not wearing heavy armor (total armor weight in pounds no more than 10+(S×4)//10), you will receive the following effects:
    • A speed bonus of +(S@5).
    • Free action if S≥25.
    • Armor-class bonuses, as follows (cumulative):
      • (S@75) if not wearing body armor.
      • (S-13)/3 if not wearing a cloak and S≥15.
      • (S-8)/3 if not wearing a shield and S≥10.
      • (S-2)/3 if not wearing a helmet and S≥4.
      • S/2 if not wearing gloves.
      • S/3 if not wearing boots.
  • If you are not wielding any melee weapons, you will receive a +S/3 bonus to-hit and to-damge and a bonus to number of attacks, as follows:
    • +1 if S≥10.
    • +2 if S≥20.
    • +3 if S≥30.
    • +4 if S≥35.
    • +5 if S≥40.
    • +6 if S≥45.
    • +7 if S=50.

    If you are wearing heavy armor, as defined above, the attack bonus is halved and the to-hit and to-damage bonuses are lost.

If you have Dodge skill, your Barehanded-combat skill is applied as a percentage bonus to your dodging probability (as described therein).

Bearform-combat

In addition to the effects described in the "Melee styles" entry under Combat, the following effects are applied if you have selected the "Bearform combat" melee style:

  • 2+S/5 blows per round
  • -S/5 to-hit
  • +S/2 melee damage

Note that in order to select Bearform combat, you must be in bear form (hence the name). Bear form has the following effects (where L is your level):

  • -5+(L/5) speed [-5-(L/5) for v2.2.6 and earlier]
  • +5+(L×2)/3 to armor class
  • +L/11 STR
  • +L/11 INT
  • +L/11 WIS
  • -1 DEX
  • +L/11 CON
  • -10 CHR
  • Free action if L≥10
  • Regeneration if L≥20
  • Resist confusion if L≥30
  • Resist nexus if L≥35
Boulder-throwing [Combat@0.4]

If S≥1, you can create boulders from granite walls via the "Tear down a wall to create boulders" option from the 'm' menu. A thrown boulder does damage (5d5+(S@80))×(S@6) and has range ((R+20)×(10+2×(S@6)))/50 to a maximum of 10+2×(S@6), where R is a STR-based adjustment (see below).

Antimagic (FF)

The Antimagic skill has the following effects:

  • If S≥1, you will be unable to cast spells, use staffs, wands or rods, or use powers from the Mindcraft, Mimicry, Thaumaturgy, Possession, Necromancy, Runecraft, Summoning, or Symbiosis skills. You will also automatically abandon any god you were following, and will not be able to take up a new god.
  • Your anti-magic field has strength S and radius 1+(S@10). "Strength" here denotes the percent chance that a monster within the field's radius will be prevented from casting a spell.
  • A wielded Dark Sword increases the strength of your anti-magic field by 10+(S@40)-X, where X is the sum of the Dark Sword's pval and to-hit, damage and armor class bonuses. The radius of the field is increased by 1+(S@4)-X/15.
  • If S≥20, you can disrupt the space-time continuum, preventing teleportation (yours and monsters').
  • If S≥25, you can detect traps; if S≥35, this will also destroy adjacent doors and traps.
Sneakiness (FF)

Your Searching and Perception abilities are increased by S+(S@(5×CM)).

Stealth (FF) [Sneakiness@0.15]

Your Stealth ability is increased by (S@25)+(S@(5×CM)).

Disarming (FF) [Sneakiness@0.1]

Your Disarming ability is increased by (S@(5×CM)).

Backstab [Sneakiness@0.05]

If you have the Backstab skill, the total damage (including all to-damage bonuses) of a melee attack on a sleeping monster that is visible to you is multiplied by 1+(S@100)//100; the total damage of a melee attack on a fleeing monster is multiplied by 1+(S@70)//100.

Stealing [Sneakiness@0.15]

The Stealing skill has the following effects (D denotes the stat index of your DEX, as shown below; W denotes the weight of the item to be stolen in tenths of a pound):

  • Your probability of stealing an item from a monster without being noticed is (S@25)+1 in 41-D+(S@29)+(W/1+(S@19))+M-Z, where M is the monster's level and Z is 10 if the monster is asleep, 0 otherwise.
  • Your probability of successfully stealing an item from a store is 11 in 40-D-(S@15)+(W×N)/(5+(S@15)), where N is the number of items to be stolen.
Dodging [Sneakiness@0.1]

Your "base dodge chance", denoted BDC, is (S@150)+Sb-(2×Wa)-Wt/100, where Sb is your Barehanded-combat skill level rounded down to the nearest integer, Wa is the total weight of worn armor (body armor, helm, gloves, boots, shield and cloak) in tenths of a pound, and Wt is the total weight of everything you are carrying in tenths of a pound. Given this, your chance of dodging a melee attack from a level-M monster is BDC-(M×5)/6 percent, and your probability of dodging a bolt attack from a level-M monster is (BDC-(M×5)/6)/3 percent.

Magic (FF)

The Magic skill has the following effects:

For sub-skills of Magic that correspond to spell schools, see the associated ToME Spell Spoiler.

Magic-Device (FF) [Magic@0.07]

The Magic-Device skill has the following effects:

  • Your Magic Device ability is increased by (S@20)+(S@(10×CM)).
  • Using a Wand/Staff of <spell-name>[M|N] is equivalent to casting the given spell with spell effect level S+M-L+1, with a minimum of 0 and a maximum of N, where L is the level of the spell on the wand/staff. See the spell spoiler for the definition of spell effect level and the effects of the spells at different spell effect levels, and for the allowed values of M and N for various spells.
Spell-power [Magic@0.2]

For spells in most spell schools, the spell effect level (see notes in the spell spoiler) is increased by S@20.

Sorcery (NG) [Magic@0.2]

The Sorcery skill has the following effects:

  • Many spells can be cast using Sorcery skill instead of the associated school skill; see notes in the spell spoiler.
  • Your max hit points are reduced by S%.
Mana (NG) [Magic@0.1]

If S≥35, your maximum mana is multiplied by 1+(S-34)//100. See the spell spoiler for notes on the effect of Mana skill on Mana spells.

Geomancy [Fire@0.45,Earth@0.45,Air@0.45,Water@0.45]

See the spell spoiler for notes on the effect of Geomancy skill on Geomancy spells.

Fire (NG) [Magic@0.1]

See the spell spoiler for notes on the effect of Fire skill on Fire spells.

Water (NG) [Magic@0.1]

If S≥30, you gain the ability to breath underwater. See the spell spoiler for notes on the effect of Water skill on Water spells.

Air (NG) [Magic@0.1]

If S=50, you gain the ability to breathe without air. [Note that unlike other sources of magical breathing, such as Cloaks of Air, this does not also confer the ability to breathe underwater.] See the spell spoiler for notes on the effect of Air skill on Air spells.

Earth (NG) [Magic@0.1]

See the spell spoiler for notes on the effect of Earth skill on Earth spells.

Meta [Magic@0.1]

See the spell spoiler for notes on the effect of Meta skill on Meta spells.

Conveyance (FF) [Magic@0.1]

See the spell spoiler for notes on the effect of Conveyance skill on Conveyance spells.

Divination (FF) [Magic@0.1]

See the spell spoiler for notes on the effect of Divination skill on Divination spells.

Temporal [Magic@0.1]

See the spell spoiler for notes on the effect of Temporal skill on Temporal spells.

Mind [Magic@0.1]

See the spell spoiler for notes on the effect of Mind skill on Mind spells.

Nature [Magic@0.1]

See the spell spoiler for notes on the effect of Nature skill on Nature spells.

Udun [Magic@0.1]

See the spell spoiler for notes on the effect of Udun skill on Udun spells.

Demonology [Magic@0.1]

The Demonology skill is gained automatically when you acquire the Demon Realm corruption. It has the following effects:

  • If S>20, you gain resist confusion.
  • If S>30, you gain resist fear.

See the spell spoiler for notes on the effect of Demonology skill on Demonology spells.

Necromancy (FF) [Magic@0.04]

The Necromancy skill has the following effects:

  • The failure rate for using Necromancy powers is reduced by (S-L)×3 percent, where L is the "spell level" of the power (subject to a CON-based minimum fail rate; see below.
  • Necromancy powers are affected as follows (P denotes the spell-power boost conferred by a Mage Staff of Power or similar equipment):
    • The effects of Horrify are based on its power level, N=(2+(S×2)/3)d4+P×2: it causes stunning for 1+(3+L/10)dN turns (where L is your experience level) and fear for 1+3d(N/2) turns. A level-M monster will resist these effects with probability M-1 in N, or M-1 in 11 if N≤10; separate checks are done for the two effects. The area of effect is a bolt if S≤20, a beam if 21≤S≤35, a ball of radius 3+S/10 if 36≤S≤45, or line of sight if S>45.
    • Raise Dead reanimates corpses in a radius of 1+S/10+P/2, and heals monsters in that radius by S×3 hit points, up to their max hit points.
    • The temporary weapon created by Necromantic Teeth lasts 200+S×3+1d(100+S×4) turns. Any random additional magic is applied as though the weapon were found on dungeon level S×2.
    • Absorb Soul lasts 50+S+1d(30+S×2) turns; each soul absorbed during that time heals you by 1+M/2+(S@40) hit points, where M is the level of the monster killed.
    • Vampirism fires S/15+P/2+1 bolt effects in the specified direction; each attempts to drain 100 hit points from the affected monster, and if successful, heals you by 100 hit points. Undead, demons, non-living monsters and monsters displayed as 'E', 'g' and 'v' are not affected.
    • After casting Death, you must kill S+1d(S/2)-S/4-1 monsters to regain life.
  • The results of a backfire from a failed use of Necromancy powers are affected as follows:
    • If you are forced into undead form, you must kill S×2 monsters to regain life.
    • If undead are summoned, they will be greater undead if S≥30.
    • If you take damage, the amount is 5dS.
Runecraft [Magic@0.12]

The mana cost of a runespell is increased by P×(S/5), where P is the sum of the difficulty modifiers of all secondary runes used in the runespell (+0 for Self and Arrow, +1 for Ray, +2 for Sphere, +3 for Armageddon, +4 for Power Surge).

[Yes, that's apparently all it does. This is generally considered a bug, and is hoped to be fixed in later versions. -ed]

Thaumaturgy (FF) (NG) [Magic@0.06]

The Thaumaturgy skill has the following effects:

  • You will have a total of (S@100) Thaumaturgy spells, receiving additional spells as your skill increases.
  • The probability of failure when casting a Thaumaturgy spell of level L is reduced by 3×(S-L) percent (subject to an INT-based minimum fail rate; see below).
Alchemy

The most important effects of the Alchemy skill are described in the Essence spoiler included in ToME's in-game documentation. Other effects are as follows:

  • A temporary artifact will revert after S×S×3 turns.
  • When extracting essences from an item, you will lose some of the essences with probability 52-S in 156. This probability is checked separately for each type of essence in the item's recipe; the usual number of extracted essences, N, is reduced to either N/2 or N/3, with equal probability.
  • The explosion from an alchemy failure does 3d(L-S) damage, where L is the object's level plus the level of the ego type, if any.
  • If you learn an item's recipe while extracting its essences (this happens with probability 1 in 3) and S≥10, you will also gain full knowledge of the item, as per a Scroll of *Identify*.
  • The various bonuses of a created item (to-hit, to-dam and armor class bonuses, and pval-based bonuses for rings and amulets) are computed as though the object appeared on dungeon level S×2.
Spirituality (FF)

Your Saving Throw ability is increased by (S@(5×CM))+X, where X is a "stat"-based adjustment using (S@37) as the "stat index" (see below).

Prayer [Spirituality@0.1,Magic@0.1]

Prayer skill is used to cast god spells; see notes in the spell spoiler for its effects. Depending on what god you worship, it can also be used to cast spells in some other schools, as detailed in the spell spoiler.

Druidistic [Spirituality@0.1,Magic@0.1]

[This skill is defined in the info files, but AFAICT it is never used in the game and no class can ever gain the skill. It is reportely a relic left over from older versions of ToME, in which it apparently gave access to spells in the Druidic realm. It is noted here solely for historical interest. -ed]

Mindcraft (FF) [Spirituality@0.1,Magic@0.1]

The Mindcraft skill has the following effects:

  • The failure rate for using Mindcraft powers is reduced by (S-L)×3 percent, where L is the "spell level" of the power (subject to a WIS-based minimum fail rate; see below).
  • If S≥40, you receive ESP for all monster types.
  • Various mindcraft powers are affected as follows:
    • Neural Blast does damage (3+(S-1)/4)d(3+S/15). It fires a beam with probability S×2 percent; otherwise, it fires a radius-zero ball (different from a bolt in that it can be shot "over" a monster at another behind it).
    • Major Displacement has range S×5; Minor Displacement has range 10.
    • Pulverise fires a ball of radius (S-20)/8+1 (or 0 if S≤20), doing damage (8+(S-5)/4)d8 at the center.
    • Mindwave does base damage S×3/2 in a radius of 2+S/10 around you if S<25. If S≥25, it does S×(1+(S-5)/10) damage to all monsters in line of sight.
    • Character Armor lasts S turns.
    • Adrenaline Channeling heals S hit points; its temporary effects (haste, heroism) last 10+1d((S×3)/2) turns.
    • Psychic Drain fires a ball of radius (S-25)/10 doing base damage (S/2)d6.
    • Telekinesis does base damage S×3 (S×4 if S≥40) in a radius of 3+S/10 around you.

    Other effects described in the in-game Mindcraft powers help file are not listed here.

Music [Spirituality@0.1,Magic@0.1]

See the spell spoiler for notes on the effect of Music skill on Music spells.

Monster-lore (FF)

The Monster-lore skill can be gained or improved by completing a Bounty quest from the Beastmaster Shanty. It has the following effects:

Summoning (FF) [Monster-lore@0.1]

The Summoning skill has the following effects (where M denotes the monster level of the corpse or totem being used):

  • Creating a totem from a corpse will fail with probability M-S percent.
  • A true totem of a non-unique monster will be destroyed upon use with probability (M×25)/S percent. (True totems of unique monsters are always destroyed upon use.)
  • A monster created from a true totem will be a pet with probability (S×130)/(M+1) percent if non-unique, or (S×70)/(M+1) percent if unique.
  • A monster created from a partial totem costs ((M×100)/S)//100 mana per turn to maintain.
Corpse-preservation [Monster-lore@0.1]

The Corpse-preservation skill can be gained by completing a Bounty quest from the Beastmaster Shanty (if you already have the skill, though, a Bounty quest won't improve it). It has the following effects:

  • A given monster will leave a corpse when killed with probability 10+(S@75) percent, unless it is of a monster type that never leaves corpses.
  • When using Possessor power to leave your body to possess a corpse, the probability of your previous-body corpse rotting on departure is 75-S-(Sp@25) percent, where Sp is your Possession skill.
Possession [Monster-lore@0.1]

The Possession skill has the following effects (where L denotes the monster level of your possessed body):

  • When leaving your body to possess a corpse, the probability of your previous-body corpse rotting on departure is 75-(S@25)-Sp percent, where Sp is your Corpse-preservation skill.
  • In order to use the "major" powers of your possessed body, you must have (S@100)≥L. Major powers include most breath, bolt and ball attacks (except fire, frost, acid and lightning), most summoning spells, the more powerful cause-wounds spells, firing rockets and the Hand of Doom.
  • Using a monster power of a possessed body will cost no mana with probability S+X/2 in M+L, where M is the base mana cost for the monster power and X is a WIS-based adjustment using the "Max wgt cap" column (see below).
  • Your maximum hit points in your possessed body will be (OH+BH+SBH)/3, where OH is your maximum hit points in your original body, BH is 20+(S@80) percent of your possessed body's maximum hit points, and SBH is the square root of BH, rounded to the nearest integer.
Symbiosis (FF) [Monster-lore@0.1]

The Symbiosis skill has the following effects:

  • The failure rate of using a symbiosis power is reduced by (S-L)×3 percent, where L is the "spell level" of the power (subject to an INT-based minimum fail rate; see below).
  • The probability of failing to charm a never-moving monster is M in S×3, where M is the monster's level.
  • The "Heal Symbiote" power heals 15+(S@35) percent of your symbiote's maximum HP level.
  • On any given turn, your symbiote might rebel and attack you if S+(2×L)<M, where L is your level and M is your symbiote's monster level. The probability of it doing so is M-(2×L)-S in 1000.
  • Your symbiote will take the damage from a given attack instead of you with probability S+5 percent.
Mimicry (FF) [Monster-lore@0.1]

The Mimicry skill has the following effects:

  • When using a Mimicry cloak (Mouse Fur, Feathers Cloak, and the like), the failure rate is reduced by (S@150) percent (subject to a minimum of 2 percent), and the duration is increased by (S@1000) turns.
  • When using other mimic powers, the failure probability is decreased by (S-L)×3 percent, where L is the "spell level" of the power (subject to a DEX-based minimum fail rate; see below), and the duration is 50+1d(50+S×2) turns (except for Invisibility, for which the duration is 10+S+1d20+P, where P is the spell-power boost conferred by a Mage Staff or Power or similar equipment).
  • The probability of resisting an abomination attack is increased by S percent.

The effects of using a Mimicry cloak are also modified by Mimicry skill, as follows:

  • Mouse Fur (mouse):
    • +5+(S/7) speed
    • +10+(S/5) melee to-hit
    • Melee to-damage bonus reduced to 20% normal
    • +10+(S/5) stealth
    • -5 STR
    • +3 DEX
    • +1 CON
    • Invisibility power if S≥30
  • Feathers Cloak (eagle):
    • -3 STR
    • +2 DEX
    • +4 CON
    • -1 INT
    • +1 WIS
    • -1 CHR
    • Flight if S≥20
    • Free action if S≥25
  • Wolf Pelt (wolf):
    • +2+(S/20) STR
    • +3+(S/20) DEX
    • -3 INT
    • -2 CHR
    • +10+(S/5) speed
    • Free action
    • Resist fear
    • See invisible if S≥15
    • Resist dark if S≥30
    • Resist confusion if S≥35
  • Spider Web (spider):
    • -4 STR
    • +1 DEX
    • +1+(S/5) INT
    • +1+(S/5) WIS
    • -5 CON
    • -10 CHR
    • +5 speed
    • Resist poison, fear and dark
    • Mountain climbing if S≥40
    • Make-web power if S≥25
  • Entish Bark (Ent):
    • -5-(S/10) speed
    • +10+S armor class
    • Resist poison and cold
    • Free action
    • Regeneration
    • See invisible
    • Sensitivity to fire
    • +S/5 STR
    • -S/7 INT
    • -S/7 WIS
    • -4 DEX
    • +S/5 CON
    • -7 CHR
    • Grow-trees power

[Note that when using the corresponding Morphic Oils, these effects are computed based on (L×2)/3 instead of S, where L is your level.]

Ability effects

Specifying how much a skill level affects an ability level, of course, just pushes the question back another stage: what effect, then, does the ability have? Here we attempt to quantitatively describe some of these effects. We denote by A the ability level of the ability in question.

Fighting

A melee attack on a monster will miss with probability (C×3)/4 in A+3×H+L, where C is the monster's armor class, L is a luck-based modifier in the range -10≤L≤10, and H is your total to-hit bonus from your weapon, STR, DEX, skill-based sources and your current mimic form, if any (this amount is displayed on the character screen as '+ To Melee Hit'); thus, the Fighting ability roughly acts as a +A//3 to-hit for melee attacks.

[NB: Actually, you will automatically hit with 5% probability and automatically miss with 5% probability; the above probability is applied the other 90% of the time. Also, if you cannot see the monster you are attacking, the probability is modified to (C×3)/4 in L+(A+3×H+1)/2.]

Bows/Throw

A ranged attack on a monster will miss with probability (C×3)/4 in A+3×H-D+L, where C is the monster's armor class, L is a luck-based modifier in the range -10≤L≤10, D is the distance to the monster, and H is your total to-hit bonus from your launcher, ammo, STR, DEX, skill-based sources and your current mimic form, if any (this amount is displayed on the character screen as '+ To Ranged Hit'); thus, the Bows/Throw ability roughly acts as a +A//3 to-hit for ranged attacks. Note that this ability is only applied when shooting ammo from a sling, bow or crossbow, and does not affect the use of boomerangs, boulders, or other thrown objects.

[NB: Actually, you will automatically hit with 5% probability and automatically miss with 5% probability; the above probability is applied the other 90% of the time. Also, if you cannot see the monster you are attacking, the probability is modified to (C×3)/4 in L+(A+3×H-D+1)/2.]

Saving Throw

With probability A percent, you will successfully avoid the following effects:

You will also resist sanity blasts from eldritch horror (CthAngband) monsters with probability A in M+10, where M is the monster's level. Failing this, you will get additional chances to save against the individual effects of the sanity blast.

Note that A is increased to a minimum of 95 if you are wearing an Amulet of Anti-Magic or other item which produces an anti-magic shell (as distinct from the antimagic field generated by Dark Swords).

Stealth

A sleeping monster will become "less sleepy" (that is, wake up or come closer to waking up) in a given turn with probability 1 in 2^(A//3). Note that the maximum allowed value of the Stealth ability is 30.

Perception

You will automatically search adjacent squares on a given turn with probability 1 in 50-A, or every turn if A≥50.

Searching

You have an A percent chance per turn spent searching to find an adjacent secret door, trap or trapped chest (separate check for each).

Disarming

In each turn spent attempting to pick the lock of a door or chest or disarm a trap or trapped chest, you will succeed with probability A-X percent, with a mininum of 2 percent, where X is an adjustment based on the difficulty of the lock/trap.

Magic Device

The amount by which some skills increase their corresponding ability depends on the class modifier for the class/ability combo (denoted CM in the skill description), which are as follows:
ClassDisarmingMagic DeviceSaving ThrowStealthSearchingPerceptionFightingBows/Throw
Axemaster127100004545
Demonologist127100004545
Haftedmaster127100004545
Polearmmaster127100004545
Swordmaster127100004545
Unbeliever127100004545
Warrior127100004545
Alchemist71390001515
Geomancer71390001515
Mage71390001515
Necromancer71390001515
Runecrafter71390001515
Sorceror71390001515
Thaumaturgist71390001515
Warper71390001515
Archer810100003045
Ranger810100003045
Assassin1510100004030
Rogue1510100004030
Bard127100002525
Loremaster127100002525
Mimic127100002525
Monk127100002525
Possessor127100002525
Summoner127100002525
Symbiant127100002525
Dark-Priest710120002020
Druid710120002020
Mindcrafter710120002020
Paladin710120002020
Priest(Eru)710120002020
Priest(Manwe)710120002020

Numeric ability values are translated to the descriptive labels you see on the character screen by dividing by the ability's scale factor X and selecting a label based on the scaled result, as depicted in the following tables. The additional number in the "Legendary" label is computed as ((A/X-17)×5)/2, so that, for instance, "Legendary[2]" represents a scaled ability value of 18, "Legendary[5]" represents a value of 19, and so forth.
AbilityScale factor
Fighting12
Bows/Throw12
Saving Throw6
Stealth1
Perception6
Searching6
Disarming8
Magic Device6
Scaled valueLabel
0-1Bad
2Poor
3-4Fair
5Good
6Very Good
7-8Excellent
9-13Superb
14-17Heroic
18+Legendary

Stat-based adjustments

Some of the effects described above include stat-based adjustments; for reference, we list here the numerical amounts of said adjustments. For some purposes (mostly table lookup), a stat value is converted internally to a stat index, as delineated in the second column.
StatStat indexMin fail rateSaving throw adjMana adjMax wgt cap (×10lb)Throw adj
3099%0053
4199%0064
5299%0075
6399%0086
7499%0097
8550%11108
9630%12119
10720%121210
11815%121311
12912%121412
131011%121513
141110%121614
15129%221715
16138%221816
17147%221917
18-18/09156%332020
18/10-18/19166%332230
18/20-18/29175%332440
18/30-18/39185%332650
18/40-18/49195%332860
18/50-18/59204%443070
18/60-18/69214%443180
18/70-18/79224%553190
18/80-18/89234%5632100
18/90-18/99243%6732110
18/100-18/109253%7833120
18/110-18/119262%8933130
18/120-18/129272%91034140
18/130-18/139282%101134150
18/140-18/149292%111235160
18/150-18/159301%121335170
18/160-18/169311%131436180
18/170-18/179321%141536190
18/180-18/189331%151637200
18/190-18/199341%161637210
18/200-18/209350%171738220
18/210-18/219360%181738230
18/220+370%191839240

Changelog and credits

2007-09-30:

Necromancy's Raise Dead power does not in fact increase max hit points.

2006-12-19:

Added "ripple-effect" skill multipliers.

2006-01-02:

Belatedly move Beaked Axes, Battle Axes and Lochaber Axes from Axe-mastery to Polearm-mastery. :-}

2005-01-09:

Added a convenience link to the 2.3.x skill spoiler.

2005-01-08:

[sound F/X: forehead repeatedly striking desk] Fix the class modifier table back to where it's supposed to be. Turns out I was misreading the table from the help files; the class modifiers for Stealth, Searching and Perception are still uniformly zero. :-}

2005-01-05:
2004-11-11:

Fixed the damage computation for Boulder-throwing, as noted by user Massimiliano Marangio of the ToME forums.

2004-09-18:

Added a note to Air that, unlike Cloaks of Air and the like, magical breathing from Air skill 50 does not also confer water breathing.

2004-09-14:

Belatedly update Bearform-combat with the changed speed bonus in 2.2.7.

2004-08-02:

Barehand-combat also provides a bonus to-hit and to-damage when not wielding weapons and not wearing heavy armor.

2004-07-05:

The Antimagic destroy-doors power also destroys traps.

2004-05-30:

Bear form actually increases INT and WIS; this is a missed change from 2.1.2, in which it decreased them.

2004-05-21:

The Saving Throw ability is not in fact capped at 95%, as noted by user amaurea of the ToME forums.

2004-05-16:

Corrected effects of Critical-hits skill, as noted by RayVuelta.

2004-05-13:

Added effect of Magic-Device skill on using wands and staffs.

2004-04-23:
2004-03-22:
2004-03-19:
2004-02-07:

Rephrase some of the notation examples to emphasize that divisions, notably those in the (S@N) scaling formula, are always rounded down to the nearest integer.

2004-01-11:
2004-01-07:

Be more specific about what counts as worn armor when computing the base dodge chance.

2003-11-30:

Added Demonblades to the list of weapons covered by Sword-mastery, as noted by Mr Tako.

2003-11-05:

Expanded historical note on Druidistic skill with information provided by user LogrusMage of the ToME forums.

2003-10-12:

Expanded and corrected the Horrify and Vampirism entries under Necromancy.

2003-10-04:

Added more cross-referencing links for the skills that affect abilities.

2003-09-07:

Added links to my new spell spoiler for all the spell schools and Prayer. I think every skill is now covered (except for Druidistic, which apparently isn't even used in the game).

2003-08-22:

Belatedly updated the class modifier table for 2.2.x. Most notably, the modifiers for Stealth, Searching and Perception are no longer uniformly zero.

2003-06-22:
2003-05-15:

Added note about mana modifiers for subrace and class to the Magic section.

2003-05-07:

Added Thaumaturgy section.

2003-05-04:
2003-03-31:

Corrected mana cost per turn for maintaining monsters summoned with partial totems, as noted by Kalirion.

2003-03-25:
2003-03-12:
2003-03-09:
2003-02-19:

Added an explanation of the number in the "Legendary[##]" ability label.

2003-02-11:

Expanded the Mindcraft skill section to cover effects on the Mindcraft powers.

2003-02-09: