Spellcasting refers to the ability of the PC to tap into Ancardia's magic field and channel it to unleash elemental attacks, heal and temporarily increase his/her capabilities or invoke other special effects. Channeling requires power points as well as some degree of corresponding spell knowledge (however, several substitutes exist for both requirements). While Wizards, Necromancers, Druids, Priests and Elementalists are best suited to employ magic as a main offensive and defensive tool, it is possible to perform spellcasting with any character.
The most common approach to gain spell knowledge is reading spellbooks. Reading takes a number of turns equal to the corresponding spell base cost plus three, and requires normal vision as well as a clear mind (you can't read in the darkness, or while blind, stunned or confused). The PC is also open to attacks from monsters and can suffer hunger issues, poison or sickness. Finally, teleportitis can cause the PC to teleport during reading, effectively interrupting the process of learning a spell.
If the PC successfully spends the required number of turns, several outcomes are possible. In case necessary checks were passed, the PC gains spell knowledge in the corresponding spell. The exact value is dependent on several factors, with PC's Learning score as the most important. If negative factors (such as spell complexity, PC's race, class and attributes) contribute too much, no spell knowledge is gained. Moreover, it is possible for the PC to suffer one additional harmful effect. The following effects can occur on spell learning failure:
- The PC is blinded for several turns.
- The PC is confused for several turns.
- The PC is stunned for several turns.
- The PC is drained of some hit points; note that this can cause death
- The PC is teleported; nothing happens on levels that forbid teleportation
- The spellbook disappears
- PC's Toughness is decreased by one
- An open pit is created on the PC's current tile, causing him/her to fall into it and take damage. Nothing happens if current tile is unsuitable for digging
- The spellbook explodes, dealing fire damage to the PC and his/her equipment
The severity of the status effects or wounds caused by the first four effects is proportional to the difficulty of the spell in question.
All spellbooks have "durability" and disappear after they are successfully read several times. This number is based on many factors, possibly including the initial B/U/C status of the book. Thus, it is recommended to bless valuable spellbooks before attempting to read them. The exception to the this rule is the artifact spellbook — the black tome of Alsophocus which will never disappear. It, however, always corrupts the reader (the amount of corruption received is based on the difficulty of the spell).
- Drinking a potion of wonder grants a small amount of spell knowledge on a random spell (all of them having equal probability); cursed potions remove that amount of knowledge from said spell if the PC already knew it, and grant a single point otherwise
- Zapping a wand of wonder forces the PC to cast a random spell, drains all power points and grants several points of the corresponding spell knowledge
- Elementalists gain knowledge in several spells on each level-up
- Bards gain knowledge in 4 randomly chosen spells upon reaching level 18
- Healers gain knowledge in Calm Monster, Cure Light Wounds, Cure Disease and Slow Poison upon reaching level 25 and at all subsequent level-ups; they also gain knowledge in Cure Serious Wounds and Neutralize Poison upon reaching level 40 and at all subsequent level-ups
- Merchants gain knowledge in Create Item upon reaching level 50
- Wizards gain knowledge in all spells upon reaching level 50
A new corruption added in version 1.2.0 forces PC to cast a spell at random intervals and acts identically to wands of wonder.
Once the PC possesses at least 1 point of spell knowledge, he/she is able to cast the corresponding spell. Two methods of casting are available in the game.
Casting from knowledgeEdit
The PC uses his attunement to the spell (i.e. spell knowledge) in order to conjure it. This uses up the amount of PP equal to effective spell cost and is considered a standard action in terms of energy cost, i.e. 1000 EP. The spell that was cast is trained (increasing its efficiency; see below) and spell knowledge is reduced.
If a spellbook is in the PC's possession, he/she may attempt to read it. The game will offer a choice of either trying to increase knowledge by actually reading, or using the spellbook to cast its corresponding spell. The latter choice will use up the amount of PP equal to 3x the usual cost, and is performed with an increased energy cost of 3000 EP (roughly equivalent to 3 turns). No spell knowledge is drained this way, but efficiency is never increased.
There are two talents that are oriented on improving book-casting throughput. Good Book Caster will replace the 3x modifier to PP cost for a 2x one, and Great Book Caster will replace it once more for a 1.5x one. This is a significant decrease if the PC is performing book-casting extensively or is aspiring to become an archmage.
Note that book-casting is an effective strategy for PCs who suffer penalties in spell learning, particularly Barbarians and Mindcrafters. A single potion/wand of wonder will allow infinite spell usage, provided the spellbook and enough PP for casting is present.
Casting from hit pointsEdit
Normally, to cast a spell the PC needs to spend the required amount of power points. If PC's current PP pool is depleted or simply not large enough to cast the spell even when full, the game will prompt whether he wishes to exhaust himself to cast it. If the player chooses to allow this, the PC will be drained of all available power points, satisfying a part of spell cost, and the remainder will be powered by hit points.
An example illustrating casting from hit points:
Thog, a trollish wizard, has 40 hit points and 5 power points. He attempts to cast Fire Bolt, which has an effective cost of 10 power points. He casts the spell successfully after choosing to be drained out of health. After casting his power points were completely drained, and he is left with (40 - (10 - 5) * 0.5) = 38 hit points.
In version 1.1.1 of the game, casting from hit points abuses the PC's Mana attribute. Since attribute changes happen relatively rarely and only 1 point of Mana is normally drained due to excessive HP-casting at each change, this penalty was not usually taken seriously. Moreover, quickly restoring power points, especially in the end-game, is almost impossible without excessive praying. Due to these facts, a lot of players chose to simply use casting from hit points whenever necessary without Mana abuse consideration.
However, the situation is drastically different in version 1.2.0 of the game, where casting from hit points also severely abuses the Willpower and Toughness attributes and reduces satiation. If PC not satiated enough there is a possibility of dying from starvation just after casting a spell (especially when book-casting Wish).
All spells in ADOM can be classified by a certain number of general characteristics. The main ones include the following:
- Casting range/area of effect
- Effect type
- Effect duration
- Spell magic school
Casting range/area of effect Edit
The spells of this group cannot be targeted and may only the PC or the environment. They are primarily utility spells, that may buff the PC (Farsight, Strength of Atlas), or otherwise provide him with insight about the game world (Revelation, Identify). The group also includes a number of unique spells that actively the change the game world (Earthquake and Wish).
The spells of this group can be cast either on the PC himself/herself or on any being in the immediate vicinity of the PC (that is, on one of the 8 surrounding tiles). This group includes a broad range of effects, such as damaging (Burning Hands), buffing/healing (Bless, Cure Light Wounds) and utility (Teleport, Invisibility).
The spells of this group require the PC to choose one of the possible 8 directions (and, sometimes, the "down" direction which casts the spell on the current tile). A bolt of energy is launched in the specified direction, traveling in a straight line and affecting everything in its path. These spells are primarily offensive (elemental bolts and Magic Missile) or utility (Stun Ray, Mystic Shovel). Several of these spells conjure a "bouncing" projectile that will be reflected off walls. This feature provides significant tactical advantage but the caster must take care not to inadvertently strike him/herself with the bouncing bolt.
Many creatures have the ability to "shrug off" bolts, negating their effects.
The spells of this group affect a whole area around the PC. The group is primarily focused on damage (Fireball, Acid Ball), but also includes very useful utility spells (Light and Darkness). One outstanding feature of ball spells is that they affect everything in the area and are not stopped by dungeon layout, which allows the PC to reach monsters from behind walls. For all ball spells their effective range is based on the Willpower attribute.
Improved Fireball is a unique spell which can be "thrown" like any missile projectile on the specified tile and will explode as a ball spell upon reaching its destination. Just like missile projectiles, Improved Fireball may not reach the specified tile if it hits anything in its path.
These spells are focused on damaging opponents and include touch, bolt and ball spells. Some spells may not be applied to all monster types, some effects may be resisted or evaded by the monsters (Burning Hands, Fire Bolt, Acid Ball).
The majority of ADOM spells produce an instant effect, like damage and healing. The effect can be applied repeatedly with additional casts.
These spells last for a certain number of turns during which they provide full benefits. These are of the "buff" and "debuff" variety. Repeated castings will not increase the magnitude of the effect, but do increase the overall duration ("stacking" castings). They do not require power points to maintain; the total cost is paid up front just as with instant spells.
Spell magic schoolEdit
These spells are typically associated with wizardry and sorcery. Arcane spellcasters (Wizards and Necromancers) have a greater chance to find arcane spellbooks and will progress with arcane spells faster.
These spells are typically associated with divine research. Clerical spellcasters (Priests, Druids and Paladins) have a greater chance to find clerical spellbooks and will progress with clerical spells faster.
The effect of the majority of the spells in ADOM is governed by a corresponding sets of formulae. These formulae are typically based on the following values:
- PC's experience level
- PC's Willpower and Mana scores
- PC's proficiency with the spell (or spell efficiency)
- PC's talents
- PC's class powers
The formulae govern the spell duration, radius and magnitude of effect (where applicable) and base casting cost.
Spell efficiency Edit
Spell efficiency shows the general experience and the degree of attunement of the PC to a certain spell. The only way to increase this characteristic is to cast the spell from PP or HP or use wands of wonder. The progression speed is based on the type of the spell (arcane or clerical) and the PC's Class.
Spell base cost Edit
Spell base cost is generally modified by the amount of spell knowledge, PC's class powers and spell efficiency:
- The base cost will be increased significantly the more spell knowledge dips below 100. Having over 100 points of spell knowledge will allow the PC to cast the spell at normal rates; anything below this level impacts the base cost.
- The spell efficiency reduction is the same for all spells — each 5 levels possessed will reduce the base casting cost by 1 point.
Spell efficiency cannot be higher than twice the PC's Learning score. Actual casting cost cannot be lower than 50% of the initial base cost. A number of special effects will also affect the casting costs:
- Chaotic PCs will cast all spells (except Wish) at half of their cost (normally minimum possible cost) on Darknight, whereas the cost for lawful characters is doubled on this day.
- The situation is reversed on Silvernight (with Wish spell included this time).
- Certain special effect rooms increase/decrease casting costs.
- Teleportation spell cost based on PC's corruption and DL of current level.
- Mana battery corruption reduces cost by 20%.
- Star signs: Dragon combat magic 10% cheaper; Salamander fire magic 20% cheaper; Wand all spells 10% cheaper for neutral casters.
- Class powers: for Wizard and Priest.