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

Magic plays a central role in the D&D game. It provides an essential dose of the fantastic for any campaign. Most players and DMs agree that magic is fun; unfortunately magic also proves inscrutable or even illogical, and arguments about magic and how it works have brought many a game to a standstill. This series explores the D&D game's singular approach to magic. This week, we'll consider some of the principles underlying D&D magic and take a look a spells and spell preparation.

Magical Basics

The rules don't include a formal definition of magic; however, when the D&D core rules (Player's Handbook, Dungeon Master's Guide and Monster Manual) discuss magic, they refer to some force or effect that somehow transcends the natural laws that govern the real world. Magic works its wonders in D&D without any discernable physical cause and often without any rational explanation. D&D magic involves tapping into some kind of mysterious force or power source and shaping it into some kind of effect that the magic wielder finds useful. Characters most often do so through spellcasting (see the next section).

Magic in the D&D game follows its own logic, and a magical effect most often works more like a legal contract than a physical law. A magical effect in the D&D game has a description that defines exactly how it works in the game. This approach has its advantages for a roleplaying game, and perhaps the most important of these is that an effect's description limits its power and impact on the game world, which helps keep magic wielders from completely dominating the game. It also allows players and DMs to be reasonably sure how any particular magical effect functions in the context of the game, and that eliminates a lot of arguments and guesswork.

The Ins and Outs of Spells

Spells represent the form of magic most readily available to player characters in the D&D game. The rules define a spell as a one-time magical effect that usually must be carefully prepared ahead of time by studying a book of spells (the wizard's approach to spells) or petitioning a divine power (the cleric's method). Spells in the D&D game come in two varieties: arcane and divine. Arcane spells are generally more versatile and potent than divine spells, but they can prove more difficult to cast (see Part Three).

The Basics of Spell Preparation

The act of preparing a spell is the first step of gathering and shaping raw magical power into a useful effect. Earlier versions of the D&D game treated preparing a spell much like committing something to memory. Once a spell was "memorized," it was ready to cast. The act of spellcasting wiped the spell from the caster's memory. In the present version of the game, preparing a spell is the first step of casting the spell, and it is the most difficult and time-consuming part of the casting. Once a spell has been prepared, the spellcaster holds the spell's potential in her mind (or body) and needs only a moment of concentration (usually along with a few words, gestures, and materials) to complete the spell and release its effects. Once cast, a spell's potential is used up, though a spellcaster can prepare the same spell more than once.

The rules governing spell preparation are fairly straightforward. Chapter 10 in the Player's Handbook explains spell preparation in considerable detail. Here are the highlights:

  • Spellcasters have limited number of spells they can use each day, as shown in the table of features for the class. For characters who prepare spells, DMs may find it best to enforce the limit by restricting the character to one session of spell preparation each day (though the character doesn't have to prepare those spells all at once; see the section on delayed spell preparation).

    The act of spell preparation is what makes the character's daily allotment of spells available for use.

  • A wizard (and most other arcane spellcasters who prepare spells) must first sleep for 8 hours to clear the mind.

    The spellcaster doesn't have to sleep for every moment of that time, but the character must rest quietly when not asleep. If the character does not need to sleep for some reason, she still must have 8 hours of restful calm before preparing any spells. For example, an elf does not sleep, but instead enters a trance for 4 hours. An elf wizard still must rest for the full 8 hours before preparing any spells.

    A character is not sleeping or resting quietly when walking around, running, or using any other form of movement. Combat, spellcasting, skill use, conversation, or any other fairly demanding physical or mental task also precludes rest. Such tasks might include breaking down a door, lifting a heavy object, reading, or writing.

    If something interrupts the spellcaster's rest, all is not lost. Instead, each interruption extends the required rest period by 1 hour. Deciding what constitutes an interruption usually isn't too hard. If the character chooses to do something (or is forced to do something) that precludes rest, then the character's rest is interrupted. Deciding when one interruption ends and the next one begins can prove a little tougher. Here are a few useful rules of thumb: A single interruption lasts until the character tries to begin resting again. If an interruption lasts an hour or more, it's best to assume the character has abandoned his current attempt at rest.

    No matter how often a character stops and resumes resting, the character must have a full hour's uninterrupted rest immediately prior to preparing spells.

  • Most divine spellcasters don't need to rest before preparing spells. Instead, they must prepare spells at a certain time of day. See pages 179-180 in the Player's Handbook and Rules of the Game: All About Clerics for details.

  • A character's ability to prepare spells is diminished when the character has cast any spells just prior to spell preparation.

    When a character begins preparing spells for the day, any spells she has cast during the past 8 hours count against the number of spells the character can prepare and cast. See page 178 in the Player's Handbook for an example.

    Here's another example of the recent casting rule: Harold, a 1st-level wizard who specializes in evocation magic, has a basic daily spell allotment of three 0-level spells and one 1st-level spell (see Table 3-17 in the Player's Handbook). Harold gains an extra 1st-level evocation spell for being a specialist and also gains a bonus 1st-level spell for Intelligence. The additions make three 0-level spells and three 1st-level spells available to Harold each day.

    Harold goes to sleep at 10 PM one evening and plans to rise 8 hours later (at 6 AM the following morning) to prepare spells. At 5:35 AM, however, a horde of goblins assaults the character's camp and Harold dispatches their leader with a magic missile spell. All is well after the attack, which is over in about 10 minutes (including some time to search the surrounding area for any additional goblins). Harold gets back to bed by 5:45; he will have to rest for an extra hour because of the interruption to his rest. The earliest he can begin preparing spells this day is 7:00 AM (his original wake-up time plus 1 hour). Assuming no further interruptions, Harold will be ready to prepare spells at 7:00 AM, however, he can prepare only two extra spells at that time because he had cast a 1st-level spell at 5:35 AM, which was within 8 hours of his spell preparation time.

What's Next?

We're out of time for this week. Next week, we'll finish our study of spell preparation and consider a few other aspects of 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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