Casting Spells

When you would cast a spell normally, roll a spellcasting check:

1d20 + your Magic Attack Bonus + your Intelligence modifier + any other applicable modifiers

Each spell has a Mana Points (MP) Cost - the total amount of mana required for the spell to take effect. Each round, a character makes a spellcasting check (as described above) and applies the result toward the spell’s cost by adding it to a mana pool. The action required for the check is the same as that listed as the spell’s casting time. If a casting check fails to meet or exceed the spell’s cost, the character must continue to cast the spell on his following turns, adding the result of each subsequent check to his mana pool. Once the amount of mana accumulated in the mana pool exceeds the spell’s Mana Points Cost, the spell takes effect.

The Price

Every time you cast a spell, the act of working with mana drains you. When casting a spell within your safe limit, the effects are minor, but casting spells or rituals above your threshold of mastery can have severe side effects. This threat to a spellcaster is called “the price”. Normally, a spell that you can safely cast deals 1 point of subdual damage for every 10 MP spent on the spell when the casting is complete (minimum 1).


A spellcaster can only safely cast a spell he knows if his magic attack bonus is equal to or greater than the spell's Threshold. The safe level limits allow a spellcaster to cast certain spells without risk of serious injury. However, with enough time and resources, a spellcaster can cast any spell he knows. If you cast a spell above your safe limit, you take lethal damage equal to twice the spell's threshold (in addition to the nonlethal damage you suffer from "the price"). If a character’s caster magic attack bonus drops for any reason, his safe limit drops accordingly.


To cast a spell or ritual, you must concentrate. If something interrupts your concentration while you’re casting, you must make a Concentration check or lose the spell or ritual. The more distracting the interruption and the higher the level of the spell or ritual you are trying to cast, the higher the DC. If you fail the check, you halve your mana pool. Simply divide your accumulated mana in two.

If you take damage while trying to cast a spell or ritual, you must make a Concentration check (DC 10 + points of damage taken + the level of the spell or ritual you’re casting). If you fail the check, halve your current mana pool (see the sidebar on this page). An event interrupts your spellcasting if it comes between when you start and complete a spell, or if it comes in response to your casting the spell (for example, an attack of opportunity provoked by the spell, or an attack made 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 + 1/2 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.

If you are affected by a spell while attempting to cast a spell of your own, you must make a Concentration check or halve your mana pool. If the spell affecting you deals damage, the DC is 10 + points of damage taken + the threshold of the spell you’re casting. If the spell interferes with you or distracts you in some other way, the DC equals the spell’s saving throw DC (or the DC the spell would have if it allowed a save) + the threshold of the spell you’re casting.

Grappling or Pinned
The only spells you can cast while grappling or pinned are those without somatic components and whose material components (if any) you have in hand. Even so, you must make a Concentration check (DC 20 + the level of the spell). If you succeed on the check, you may make one final spellcasting check to attempt to complete the spell. If you do not meet the spell’s Mana Threshold, then the spell automatically fails.

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 deck 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 halve your mana pool.

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 halve your mana pool.

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. In wind-driven hail, dust, or debris, the DC is 10 + the level of the spell you’re casting. In either case, you halve your mana pool if you fail the Concentration check. If the weather is caused by a spell, use the rules in the previously described Spells subsection.

Casting Defensively
If you want to cast a spell without provoking any attacks of opportunity during a particular round of casting, 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.

If you want to cast a spell while entangled in a net or by a similar magical effect, you must make a DC 15 Concentration check. You lose the spell if you fail.

Spellcasting in Armor
Armor generally interferes with a spellcaster’s ability to cast spells, reducing flexibility, awareness, and simply being cumbersome. When casting a spell that has somatic components (either normally or as a ritual), the caster applies the armor’s armor check penalty on spellcasting and ritual casting checks. If the spellcaster is not proficient with the armor, he applies twice the penalty.

Spell Failure

Whenever the unadjusted roll of your casting check is equal to or less than 4, you fail to control the mana, losing focus and allowing the energy you’ve harnessed to slip away. Subtract your unmodified die roll from your mana pool. If you are casting a spell above your safe threshold, subtract double the spell's threshold from your mana pool as well. If this brings your mana pool to a negative number (either because you’ve just begun casting the spell or because successive failures have depleted your mana pool over a number of rounds), the result is a spectacular failure.

A spectacular failure means the intended magic goes awry, usually with some small or minor effect. The magical field the caster tried to grasp and control snaps back, having an unpredictable effect on someone or something nearby. In any event, the caster takes the normal nonlethal or lethal damage from casting the spell.

To determine the effect of the failure, roll a d20 and consult the table below. If you are casting a spell above your safe threshold, add the difference between your magic attack bonus and the spell's threshold before consulting the table.

d20 Result
1-2 The caster is stunned for 1d6 rounds.
3-4 Spell instantly takes effect, but strikes the caster or an ally instead of the intended target, or a random target nearby if the caster was the intended recipient.
5-6 Failed casting imposes a –10 penalty on the caster’s next casting check
7-8 A surge of uncontrolled magical energy deals 1d6 points of damage per the spell's threshold to the caster.
9-10 Failed casting imposes a –5 penalty on the caster’s next three casting checks.
11-12 The next spell the caster successfully casts automatically fails and results in a spectacular failure.
13-14 Failed casting imposes a –2 penalty on the caster’s next ten casting checks
15-16 Caster becomes sickened for 1d10 rounds
17-18 The next spell or ritual the caster successfully casts has all variable factors halved (including duration, area, range, damage, and so on)
19-20 Caster becomes exhausted
More than 20 Roll twice on the chart and combine the results

Cautious Casting

A character can reduce the failure range of a spell by an amount up to his Magic Attack Bonus, to a minimum of 1. For every point by which a spellcaster reduces the failure range, he takes a –2 circumstance penalty on his casting check. Note that this penalty can reduce your casting check to 0 but not below 0.

Hasty Casting

To cast a spell hastily, a spellcaster increases the failure range of a spell by a certain amount. For every point spent to increase the failure range, the spellcaster gains a +2 circumstance bonus on his casting check. The spellcaster cannot increase the failure range by more than his Magic Attack Bonus.

Preparing Spells in Advance

A spellcaster can start casting a spell in advance, storing the free mana in his mana pool. To do so, he begins to cast the spell as normal, but before he meets the spell’s MP cost, he must stop casting. (If the spell’s mana threshold is exceeded, even accidentally, the spell is cast as normal.) Locking the spell into place, he records how much mana he has accumulated on his character sheet for the purpose of casting that spell.

A spellcaster can only prepare spells in advance that are within his safe level limit. As well, preparing spells in this way is time consuming, with each spellcasting check taking 1 minute to carefully draw mana and ready the spell. If he so chooses, a caster can prepare another spell in advance (or the same spell a second time). A spellcaster can hold a number of spells in his mind equal to his Intelligence modifier.

At any point, a spellcaster can retrieve a prepared spell from memory and ready it for casting. He makes a spellcasting check as normal, but now needs to only exceed the spell’s remaining Threshold in order to successfully cast the spell. A spellcaster can also choose to "forget" a spell previously prepared in advance if no longer needed, or if he wants to prepare another spell in its place. If he chooses to do this, the mana spent on the forgotten spell is lost.

Changing Spells in the Middle of Casting

Sometimes it’s necessary to change a spell in the middle of casting it. There are two ways to do this - the first way is to adjust the spell you are already casting (by adding or removing spell options or metamagic feats, for example). If the change adds to the MP of the spell, you must continue casting as normal to reach the MP cost. If your adjustments lower the MP cost below the amount of mana in your mana pool, the spell is immediately cast. You can only choose to adjust your spell in this way as a swift action. You pay the price of the spell's current cost when it is cast, not the cost of the original spell.

The other way to change the spell is to completely change what spell you are casting- perhaps the situation has changed, and the spell you have been casting is no longer going to be effective. In this situation, any mana you have already drawn toward casting the initial spell is not a complete loss, but can be transferred to another spell instead. To do so, pay the price (lethal or nonlethal damage) of the original spell you had intended to cast, and halve your mana pool. The remaining mana can then be applied to the new spell you want to cast. In some cases, it’s possible that you might end up with enough mana in your newly-halved mana pool to cast the new spell automatically. If this is the case, you still need to make a casting check to complete the spell.

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