View source for Fast Cast Spontaneous Spell

Magi can '''Fast-Cast''' spells in response to an attack or other emergency.  For example, a magus could fast-cast a spell to parry aside an enemy's sword, to to block a hostile spell, or to save himself from falling off a bridge.

Whenever a magus comes under attack or is suddenly endangered, he can try to defend himself by fast-casting.  Success is not guaranteed; first, the magus needs to react in time, and then needs to cast an appropriate spell of high enough [[Spell Level|level]].

== What Spells can be Fast-Cast ==

In [[ArM5]], the only spells a magus can fast-cast are [[Spontaneous Spell|spontaneous spells]], or spells he has [[Spell Mastery|mastered]] and given the "Fast Casting" [[Mastery Ability]].  Ordinary [[Formulaic Magic|Formulaic]] and [[Ritual]] spells take too long.

== Fast Casting and Initiative ==

You do not need to roll [[Initiative]] to fast-cast a spell. You can fast-cast at any time, usually in response to something bad happening like getting attacked or having a spell cast at you. You can do this even at the start of battle before your first turn has come up yet. If you fast-cast, that's basically a free action and it does not stop you taking another action, even casting another spell, that combat round.

===  Fast-Casting Speed Roll ===

Although you can attempt a fast-cast spell at any time, you aren't always fast enough to actually defend against the attack. That's what the fast-casting speed roll is for ([[ArM5]], page 83): to determine if you fast-cast the spell in time for it to do any good. As noted on p. 83, if you fail the speed roll, you can choose to abort the spell, which is probably a good idea because there is no point in risking fatigue loss or a botch if it's too late for your spell to protect you.

== Casting Total and Level ==

Fast-Casting is always done with a firm voice and bold gestures.  The caster gets the normal bonuses for these [[Words and Gestures]] ([[ArM5]], page 83).  There is an additional penalty to the [[Casting Total]] due to fast-casting, and fast-cast spells incur extra [[Botch die|botch dice]] ([[ArM5]], page 83).

Against physical attacks, the Fast-Cast spell must meet the normal [[Spell Level|level]] needed to stop that attack, according to the [[Spell Guidelines]].  For example, to deflect a single blow from a wooden weapon using a fast-cast [[Rego]] [[Herbam]] spell, the magus would need to duplicate the effects of ''Repel the Wooden Shafts'' ([[ArM5]], page 138), at the same [[Spell Level]].

Against spells, a Fast-Cast defensive spell of one-half the [[Spell Level|level]] of the incoming spell is usually sufficient to defend against it, although the attacking spell still succeeds and has effects.  The [[Storyguide]] should use his or her best judgment as to whether a given Fast-Cast defensive spell will be effective, and whether its level needs to be slightly above or below this rule of thumb.

== References ==

* ''[[Ars Magica Fifth Edition]]'', Chapter Seven: Hermetic Magic, "Spellcasting Options - Spontaneous Spells - Fast Casting", p. 83
* ''[[Ars Magica Fifth Edition]]'', Chapter Seven: Hermetic Magic, "Spellcasting Options", "Words & Gestures" Insert, p. 83

=== Related Topics ===

* [[Spontaneous Spell]]
* [[Spell Mastery]]

===  Legacy Page  ===
The history of this page before August 6, 2010 is archived at [[Legacy:fast_cast_spontaneous_spell]]
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