Rules of the Game
Magical Oddities (Part Two)
By Skip Williams

Last week we touched on the basics of D&D magic, spells, and spell preparation. This week, we'll conclude our look at spell preparation and explore a few more issues concerning spells.

Spell Preparation Requirements and Options

Once a character sleeps 8 hours or reaches the designated time of day, the way is clear for preparing spells -- provided the spellcaster can clear a few more hurdles:

  • Spell preparation requires concentration.

    In this case, concentration requires freedom from overt distractions. The rules include a short list of distractions that prevent spell preparation: combat nearby, exposure to inclement weather, injury, or a failed saving throw (see page 178 in the Player's Handbook), but otherwise leave the DM free to decide when distractions are sufficient to prevent spell preparation. Here are some additional rules of thumb.

    Combat nearby interferes with spell preparation when the DM decides that the character has a reasonable chance to become involved in the fight. This occurs whenever the character is within range of a foe's ranged attacks or spells and one of those spells or ranged attacks is directed at the character or anywhere the character could reach with a double move. Likewise, a character could reasonably become involved in a fight whenever the character finds himself within a double move of any ally or enemy that is attacking or being attacked during the fight. Use either the character's speed or the enemy or ally's speed, whichever is greater, to determine the distance. These are guidelines, not hard and fast rules. The key element is the potential danger to the character attempting to prepare spells and the character's ability to perceive that danger. If the character trying to prepare spells remains blissfully unaware of the fight, it's a good bet the fight won't distract the character from spell preparation.

    Weather is inclement and sufficiently harsh to disrupt spell preparation when it can damage, fatigue, or otherwise hinder the character. As a rule of thumb, I recommend that winds of moderate or stronger force (see Table 3-24 in the Dungeon Master's Guide), interfere with spell preparation, at least for any character who uses spellbooks to prepare spells. Characters who don't have to read spellbooks probably don't have to worry about spell preparation until the wind reaches at least strong force.

Precipitation of any kind intense enough to reduce vision or provide concealment also interferes with spell preparation, as does heat or cold intense enough to deal damage (lethal or nonlethal) or to cause the character to become fatigued or exhausted.

DMs might want to make some exceptions to these rules for divine spellcasters who revere nature or the elements or who are associated with nature or elemental deities. A druid, for example, might not find even a severe thunderstorm distracting when it comes to preparing spells.

  • A character needs 1 hour to prepare his daily allotment of spells, no matter how many spells that might be.

    The rules don't say what happens when spell preparation is interrupted; however, the rules say that the minimum time to prepare any spell is 15 minutes (the time required to achieve the correct mental state). Therefore, a DM could decide that a spellcaster prepares no spells at all if interrupted less than 15 minutes after commencing spell preparation. Otherwise, a character prepares about a quarter of his daily spell allotment every 15 minutes spent in preparation until all his daily spells are prepared.

    Since a spellcaster doesn't have to prepare all his spells at once (see the next section), being interrupted during spell preparation doesn't have much effect on a character except that the character must function with less than his full daily allotment for a time.

  • A character need not prepare all his spells at once.

    A character who prepares spells can opt to halt spell preparation at any time. If he does so, he prepares about a quarter of his available spell slots for every 15 minutes spent in preparation (see the previous section). All the character's remaining spell slots still can hold spells during the current day (subject to the rule on recent spellcasting, see the section on rest), but the character cannot fill them with spells until he takes the time to prepare spells for them. See page 178 in the Player's Handbook for details.

    A character might find it handy to leave a few spell slots empty at the start of the day so he can fill them later when he has a better idea what spells he might need. When filling the empty slots, the character still needs the proper environment (see the previous sections) and at least 15 minutes of preparation time.

  • When initially preparing spells for the day, a character can fill any spell slots used up the previous day (subject to the recent casting limit rule). The character also can replace any unused spells left over from the previous day. The character doesn't have the option to replace previously prepared spells if he chooses to wait and prepare some spells later in the day.

  • When selecting a spell to place into an available spell slot, a character can choose any spell of the slot's level or lower, provided that the chosen spell is one the character normally can prepare.

    This option allows you to load up with a few extra copies of your favorite spell. It's also a good way to use spell slots that you have available, but of a level too high for you. For example, Cinda, an 11th-level wizard with an Intelligence score of 15 normally has a single 6th-level spell slot available each day. A wizard, however, needs an Intelligence score of at least 16 to cast a 6th-level spell (see page 56 in the Player's Handbook). Fortunately, Cinda can place a spell of 5th level or lower into the 6th-level spell slot. The spell functions at its usual spell level despite being in a higher-level slot. For example, if Cinda places a 5th-level cone of cold spell in her otherwise unusable 6th-level spell slot, the spell has a saving throw DC of 17 (10 + spell level + Cinda's Intelligence modifier of +2). All other variables or characteristics that depend on the example spell's level, such as its ability to penetrate a globe of invulnerability effect, function at the spell's original level (5th).

Instinctive Spellcasting

Some spellcasters (such as sorcerers and bards) have a natural talent for spellcasting and essentially employ a spell merely by completing its final portion. An instinctive caster readies spells each day rather preparing them (see page 179 in the Players Handbook).

To ready spells for the day, an instinctive caster must first rest for 8 hours. This works exactly as described in Part One for characters who prepare spells.

After waking, an instinctive caster requires 15 minutes of concentration to make all his daily spell slots available. The rules don't specifically say so, but this works much like preparing spells, at least in terms of the environment required. The rules don't say what happens if the character is interrupted, but DMs may want to rule that an interruption foils the attempt to ready spells and that the character can simply try again when conditions permit.

Spontaneous Spellcasting

Clerics (and other divine spellcasters, such as druids) can cast spells spontaneously; see page 32 in the Player's Handbook and Rules of the Game: All About Clerics {{link}}. To spontaneously cast a spell, a character uses up a previously prepared spell and casts the spontaneous spell instead, rechanneling the prepared spell's raw magical force or energy into the new spell. Doing so doesn't require any special effort, but the character needs a prepared spell to convert into the desired spell. I suppose the character could use an empty spell slot the character has saved from her initial spell preparation for the day (see the previous section) for the spontaneous spell, but that doesn't match the spirit (or the letter) of the rule.

Spells and Saves

Spells that harm, alter, hinder, or otherwise affect a subject usually allow saving throws to resist their effects. Kinds of saving throws and the results of a successful save are detailed on pages 176 and 177 of the Player's Handbook and in Rules of the Game: Reading Spell Descriptions. People overlook a few other things about saves.

What the Subject Knows: Whenever a spell (or other magical effect) that has obvious physical results affects a subject that has a Wisdom score, the subject is aware of those effects. As an unofficial rule of thumb, obvious physical effects include damage, transformation, disability, or other effects that the subject can see, hear, feel, taste, smell, or otherwise perceive or deduce using the normal human senses. The subject notices the spell's effects even if the subject fails a saving throw (if one is allowed). If the magical effect kills the subject or renders the subject unconscious, the DM might decide that the subject doesn't notice what hit her. If the attack happens when the victim is flat-footed and the caster is unseen or unnoticed, a DC 15 Wisdom, Spot, or Listen check (whichever the DM thinks is most appropriate) can determine if the subject realizes what's happening before losing consciousness. As always, adjust the DC up or down according to the circumstances.

Even when the subject notices obvious physical effects, she does not necessarily know that a spell or other magic was involved. A Spellcraft check with a DC of 20 + the spell level reveals the spell. When the effect is not a spell, assign it a level based on a spell with a similar effect. A dragon's breath weapon, for example, might be the equivalent of a 3rd- or 4th-level spell for this purpose. The DM might waive the Spellcraft check when the spell or effect is something the character has used or witnessed before.

When a spell or other magic has no obvious physical effects, a subject that fails a saving throw remains unaware of the assault. If the subject makes a successful saving throw, she feels a hostile tingle. This is true whether the successful save completely negates the spell or results in a reduced or partial effect. The subject knows she has shaken off some hostile magic, but gains no clues about what the effect was or what its source might be.

What the Caster Knows: When a spell has a target entry, the caster knows when the target makes a successful saving throw or not. The caster immediately senses when a target makes a successful saving throw and likewise knows if a target has failed a saving throw by virtue of not noticing a successful saving throw. When a spell can affect several targets at once, the caster notes each successful or failed saving throw.

The caster does not sense successful or failed saving throws when a spell has an area or effect entry instead of a target entry.

For magical effects that aren't presented in the same format as a spell, refer to a similar spell to determine if the user can sense a successful or failed saving throw. For example, a supernatural or spell-like ability that works just like the charm monster spell is a targeted effect and the user knows when the target's save succeeds or fails.

What's Next?

That concludes our look at spell preparation. Next week, we'll explore more about spells and spellcasting.

About the Author

Skip Williams keeps busy with freelance projects for several different game companies and was the Sage of Dragon Magazine for many years. Skip is a co-designer of the D&D 3rd Edition game and the chief architect of the Monster Manual. When not devising swift and cruel deaths for player characters, Skip putters in his kitchen or garden (rabbits and deer are not Skip's friends) or works on repairing and improving the century-old farmhouse that he shares with his wife, Penny, and a growing menagerie of pets.


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