Casting Spells

The Basics

A spell is a one-time magical effect. Spells come in two types: arcane (such as those cast by bards, sorcerers, and wizards) and divine (such as those cast by clerics, druids, and experienced paladins and rangers). Some spellcasters select their spells from a limited list of spells known, while others have access to a wide variety of options.

Most spellcasters prepare their spells in advance—whether from a spellbook or through devout prayers and meditation— while some cast spells spontaneously without preparation.

Despite these different ways that characters use to learn or prepare their spells, when it comes to casting them, the spells are very much alike.

Cutting across the categories of arcane and divine spells are the eight schools of magic. These schools represent the different ways that spells take effect.

Spell Slots

Whether a spellcaster prepares their spells ahead of time or casts them spontaneously, spells are cast using a concept called Spell Slots. Each in game day, a spellcasting character gets a certain number of these spell slots to cast their spells. For example, a 4th-level Sorcerer has six 1st-level spell slots and three 2nd-level spell slots. This allows the sorcerer to cast six 1st-level spells and three 2nd-level spells during that day.

A spellcaster who must prepare their spells (such as a Cleric or Wizard) fills these slots at the beginning of the day and can only cast the spells they have chosen for that day (see Preparing Spells From a Spellbook and Preparing Divine Spells and Spell Access). Conversely, spontaneous spellcasters know a limited number of spells but can cast any of these spells known at any time, provided they have an available spell slot of the same spell level or higher.

Ability Scores and Spellcasters

The ability that your spells depend on—your key ability score—is related to what spellcasting class (or classes) you have levels in, such as Intelligence (wizard), Wisdom (cleric), and Charisma (sorcerer). The modifier for this ability is referred to as your key ability modifier.

If your character’s key ability score is 9 or lower, you can’t cast spells from that class. A high ability score grants bonus spells to a spellcaster.

How To Determine Bonus Spells

Your key ability score grants you additional spell slots based on your key ability modifier as it related to the level of spells.

For those interested, the exact formula for determining how many bonus spells a character gets for any given spell level is as follows: (Ability Modifier – Spell Level + 1) ÷ 4, rounded up.

For the rest of us, Table: Ability Modifiers and Bonus Spells is provided as a reference chart.

If your level is not high enough to casts spells of a given level, you do not gain bonus spell slots of that spell level, even if your ability score is high enough to grant those slots. You simply aren’t able to cast spells of that levels.

Casting Spells

Whether a spell is arcane or divine, and whether a character prepares spells in advance or chooses them on the spot, casting a spell works the same way.

Choosing A Spell

First you must choose which spell to cast. If you’re a prepared spellcaster, you select from among spells prepared earlier in the day and not yet cast (see Preparing Spells From a Spellbook and Preparing Divine Spells and Spell Access).

If you’re a spontaneous spellcaster, you can select any spell you know, provided you are capable of casting spells of that level or higher.

To cast a spell, you must be able to speak (if the spell has a verbal component), gesture (if it has a somatic component), and manipulate the material components or focus (if any). Additionally, you must concentrate to cast a spell.

If a spell has multiple versions, you choose which version to use when you cast it. You don’t have to prepare (or learn, in the case of a spontaneous spellcaster) a specific version of the spell.

Once you’ve cast a prepared spell, you can’t cast it again until you prepare it again. (If you’ve prepared multiple copies of a single spell, you can cast each copy once.) If you’re a spontaneous spellcaster, casting a spell counts against your daily limit for spells of that spell level, but you can cast the same spell again if you haven’t reached your limit.

Concentration

To cast a spell, you must concentrate. If something interrupts your concentration while you’re casting, you must make a concentration check or lose the spell. The more distracting the interruption and the higher the level of the spell you are trying to cast, the higher the DC is. If you fail the check, you lose the spell just as if you had cast it to no effect.

When you make a concentration check, you roll d20 and add your caster level and the ability score modifier used to determine bonus spells of the same type. For example, clerics would add Wisdom to a concentration check while wizards would add Intelligence.

Injury

If you take damage while trying to cast a spell, you must make a concentration check (DC 10 + points of damage taken + the level of the spell you’re casting). If you fail the check, you lose the spell without effect. The interrupting event strikes during spellcasting if it comes between when you start and when you complete a spell (for a spell with a casting time of 1 full round or more) or if it comes in response to your casting the spell (such as an attack of opportunity provoked by the spell) or a contingent attack (such as a readied action).

If you are taking continuous damage, half the damage is considered to take place while you are casting a spell. You must make a concentration check (DC 10 + ½ the damage that the continuous source last dealt + the level of the spell you’re casting). If the last damage dealt was the last damage that the effect could deal then the damage is over, and it does not distract you.

Repeated damage does not count as continuous damage.

Spell

If you are affected by a spell while attempting to cast a spell of your own, you must make a concentration check or lose the spell you are casting. If the spell affecting you deals damage, the DC is 10 + the damage taken + the level of the spell you’re casting.

If the spell interferes with you or distracts you in some other way, the DC is the spell’s saving throw DC + the level of the spell you’re casting. For a spell with no saving throw, it’s the DC that the spell’s saving throw would have if a save were allowed (10 + spell level + caster’s ability score).

Grappling or Pinned

Casting a spell while you have the grappled or pinned condition is difficult and requires a concentration check (DC 10 + the grappler’s CMB + the level of the spell you’re casting). Pinned creatures can only cast spells that do not have somatic components.

Vigorous Motion

If you are riding on a moving mount, taking a bouncy ride in a wagon, on a small boat in rough water, below-decks in a storm-tossed ship, or simply being jostled in a similar fashion, you must make a concentration check (DC 10 + the level of the spell you’re casting) or lose the spell.

Violent Motion

If you are on a galloping horse, taking a very rough ride in a wagon, on a small boat in rapids or in a storm, on deck in a storm-tossed ship, or being tossed roughly about in a similar fashion, you must make a concentration check (DC 15 + the level of the spell you’re casting) or lose the spell.

If the motion is extremely violent, such as that caused by an earthquake, the DC is equal to 20 + the level of the spell you’re casting.

Violent Weather

You must make a concentration check if you try to cast a spell in violent weather. If you are in a high wind carrying blinding rain or sleet, the DC is 5 + the level of the spell you’re casting. If you are in wind-driven hail, dust, or debris, the DC is 10 + the level of the spell you’re casting. In either case, you lose the spell if you fail the Concentration check. If the weather is caused by a spell, use the rules in the Spell subsection above.

Casting Defensively

If you want to cast a spell without provoking any attacks of opportunity, you must make a concentration check (DC 15 + the level of the spell you’re casting) to succeed. You lose the spell if you fail but do not provoke an attack.

Entangled

If you want to cast a spell while entangled in a net or by a tanglefoot bag or while you’re affected by a spell with similar effects, you must make a  concentration check (DC 15 + the level of the spell you’re casting) to cast the spell. You lose the spell if you fail.

Counterspells

It is possible to cast any spell as a counterspell. By doing so, you are using the spell’s energy to disrupt the casting of the same spell by another character. Counterspelling works even if one spell is divine and the other arcane.

How Counterspells Work

To use a counterspell, you must select an opponent as the target of the counterspell. You do this by choosing the ready action. In doing so, you elect to wait to complete your action until your opponent tries to cast a spell. (You may still move your speed, since ready is a standard action.)

If the target of your counterspell tries to cast a spell, make an appropriate skill check (Arcane Lore for arcane spells, Theology for divine spells, or Natural Lore for spells directly related to nature) with a DC of 15 + the spell’s level. This check is a free action. If the check succeeds, you correctly identify the opponent’s spell and can attempt to counter it. If the check fails, you can’t do either of these things.

To complete the action, you must then cast the correct spell. As a general rule, a spell can only counter itself. If you are able to cast the same spell and you have it prepared (if you prepare spells), you cast it, altering it slightly to create a counterspell effect. If the target is within range, both spells automatically negate each other with no other results.

Counterspelling Metamagic Spells

Metamagic feats are not taken into account when determining whether a spell can be countered

Specific Exceptions

Some spells specifically counter each other, especially when they have diametrically opposed effects.

Dispel Magic as a Counterspell

You can use dispel magic to counterspell another spellcaster, and you don’t need to identify the spell he or she is casting. However, dispel magic doesn’t always work as a counterspell.

Caster Level

A spell’s power often depends on its caster level, which for most spellcasting characters is equal to your class level in the class you’re using to cast the spell.

You can cast a spell at a lower caster level than normal, but the caster level you choose must be high enough for you to cast the spell in question, and all level-dependent features must be based on the same caster level.

In the event that a class feature, domain granted power, or other special ability provides an adjustment to your caster level, that adjustment applies not only to effects based on caster level (such as range, duration, and damage dealt) but also to your caster level check to overcome your target’s spell resistance and to the caster level used in dispel checks (both the dispel check and the DC of the check).

Caster Level Checks

To make a caster level check, roll 1d20 and add your caster level (in the relevant class). If the result equals or exceeds the DC (or the spell resistance, in the case of caster level checks made for spell resistance), the check succeeds.

Spell Failure

If you ever try to cast a spell in conditions where the characteristics of the spell cannot be made to conform, the casting fails and the spell is wasted.

Spells also fail if your concentration is broken and might fail if you’re wearing armor while casting a spell with somatic components.

The Spell’s Result

Once you know which creatures (or objects or areas) are affected, and whether those creatures have made successful saving throws (if any were allowed), you can apply whatever results a spell entails.

Special Spell Effects

Many special spell effects are handled according to the school of the spells in question Certain other special spell features are found across spell schools.

Attacks

Some spell descriptions refer to attacking. All offensive combat actions, even those that don’t damage opponents are considered attacks. Attempts to turn or rebuke undead count as attacks. All spells that opponents resist with saving throws, that deal damage, or that otherwise harm or hamper subjects are attacks. Spells that summon monsters or other allies are not attacks because the spells themselves don’t harm anyone.

Bonus Types

Usually, a bonus has a type that indicates how the spell grants the bonus. The important aspect of bonus types is that two bonuses of the same type don’t generally stack. With the exception of dodge bonuses, most circumstance bonuses, and racial bonuses, only the better bonus works (see Combining Magical Effects). The same principle applies to penalties—a character taking two or more penalties of the same type applies only the worst one.

Bringing Back the Dead

Several spells have the power to restore slain characters to life.

When a living creature dies, its soul departs its body, leaves the Material Plane, travels through the Astral Plane, and goes to abide on the plane where the creature’s deity resides. If the creature did not worship a deity, its soul departs to the plane corresponding to its alignment. Bringing someone back from the dead means retrieving his or her soul and returning it to his or her body.

Level Loss

Any creature brought back to life usually loses one level of experience. The character’s new XP total is midway between the minimum needed for his or her new (reduced) level and the minimum needed for the next one. If the character was 1st level at the time of death, he or she loses 2 points of Constitution instead of losing a level.

This level loss or Constitution loss cannot be repaired by any mortal means, even wish or miracle. A revived character can regain a lost level by earning XP through further adventuring. A revived character who was 1st level at the time of death can regain lost points of Constitution by improving his or her Constitution score when he or she attains a level that allows an ability score increase.

Preventing Revivification

Enemies can take steps to make it more difficult for a character to be returned from the dead. Keeping the body prevents others from using raise dead or resurrection to restore the slain character to life. Casting trap the soul prevents any sort of revivification unless the soul is first released.

Revivification against One’s Will

A soul cannot be returned to life if it does not wish to be. A soul knows the name, alignment, and patron deity (if any) of the character attempting to revive it and may refuse to return on that basis.

Combining Magical Effects

For combining the effects of multiple spells, refer to the rules on Combining Magical Effects.