Last week, we examined illusion subschools and considered what an illusion spell's subschool says about what the spell can do. This week, we'll continue our look at illusion basics by considering two other key elements in an illusion spell.
Aiming Illusion Spells
As noted in Part One, a spell's area, target, or effect entry determines how and where the caster can aim the spell.
Area: Any spell that has an area entry fills some volume of space when it takes effect. Most spell areas are immobile after they're cast, but be on the lookout for area spells that are portable. The silence spell, for example, is an illusion spell with an area (an emanation) that can be centered on a mobile object or on a creature so that the spell's effects move along with it.
Illusion spells that have area entries often affect subjects that are in the area at the time the spell is cast or that enter the area while the spell lasts. This is particularly true of illusion spells from the pattern subschool, such as rainbow pattern. Subjects that merely see the pattern from outside the area it fills aren't affected.
Other illusion spells create a false sensation throughout the area or alter an area's sensory properties. Spells from the glamer subschool often have areas that work this way. Examples include hallucinatory terrain and mirage arcana. Anyone with line of sight to such a spell's area can notice whatever sensation the spell produces, even from outside the spell's area (provided that the creature has the appropriate senses). For example, if you use a hallucinatory terrain spell to make an empty patch of sand look like an oasis, anyone who can see that patch of sand sees the illusion you have created. Audible illusions might remain audible even without line of sight. For example, if you create the image of a creaky windmill, creatures nearby can hear the mill creaking even when it's too dark to see the mill.
Effect: A spell with an effect entry produces something. An illusion spell with an effect entry produces a sound, smell, texture, taste, visual image, or some combination of the five. Spells from the figment subschool often have effect entries that look a great deal like areas. The effect entry specifies a maximum volume for the image (or images) the spell produces.
You can make images you create move around, but only with the volume limit set for the spell. For example, you could use a major image spell to create an illusory guard that paces around a room, but you can't make your illusory guard accompany you wherever you go (unless you stay inside the spell's volume limit).
As with an area illusion, anyone nearby can perceive an effect illusion. For instance, the marching guard from the previous example can be seen and heard just as a real guard could be.
Target: When a spell has a target entry, you select one or more recipients to receive the spell (there might be limits to the targets you can select, see Rules of the Game: Reading Spell Descriptions, Part Five). In any case, all your targets must be in range and you must have line of effect to them. If you don't have line of sight to a recipient, you still can select it as a target if you can touch it.
Once a target receives a spell, the spell's effect moves along with it.
Because glamer spells change the recipient's sensory properties, most glamers have target entries (often the caster or something the caster touches). Phantasms, which affect the recipient's mind, also usually have target entries.
As with illusion spells that have area or effect entries, anyone with line of sight to the recipient of a targeted illusion spell perceives the illusion the spell creates (except for phantasms, as noted earlier). For example, the invisibility spell makes a subject vanish from sight. Anyone looking at the space containing the invisible subject sees nothing (or at least does not see the subject).
Saving Throws and Illusion Spells
Most spells' saving throw entries are self-explanatory; however, some illusion spells have a kind of saving throw that causes a few problems.
Most figment spells (and a few other illusions) have saving throw entries that read: "Will disbelief (if interacted with)." This can prove maddeningly vague, especially when someone decides to start splitting hairs. Anyone who has played the game for more than a few hours knows what a Will save is. But what is the effect of disbelief and what constitutes interaction?
From pages 173-174 of the Player's Handbook:
Saving Throws and Illusions (Disbelief ): Creatures encountering an illusion usually do not receive saving throws to recognize it as illusory until they study it carefully or interact with it in some fashion. For example, if a party encounters a section of illusory floor, the character in the lead would receive a saving throw if she stopped and studied the floor or if she probed the floor.
A successful saving throw against an illusion reveals it to be false, but a figment or phantasm remains as a translucent outline. For example, a character making a successful saving throw against a figment of an illusory section of floor knows the "floor" isn't safe to walk on and can see what lies below (light permitting), but he or she can still note where the figment lies.
A failed saving throw indicates that a character fails to notice something is amiss. A character faced with proof that an illusion isn't real needs no saving throw. A character who falls through a section of illusory floor into a pit knows something is amiss, as does one who spends a few rounds poking at the same illusion. If any viewer successfully disbelieves an illusion and communicates this fact to others, each such viewer gains a saving throw with a +4 bonus.
Page 173 in the Player's Handbook covers disbelief in detail. The text there can be summed up fairly easily. If you make a successful saving throw against an illusion effect and disbelieve it, you stop perceiving the illusion and it has no effect on you at all. Illusions from the figment or glamer subschools, however, remain behind as faint, translucent outlines even after you successfully disbelieve them. These see-through remnants have no effects on you at all, but serve to remind you that the illusion is there. It also reminds you of those things with which other less perceptive individuals might have to deal. The rules use an illusory section of floor (presumably a figment) as an example. If you have disbelieved the illusion, you see the floor (light permitting) as it is; that is, with a gaping hole in it. You also see the outlines of the illusion, however, which can prove handy when an unsuspecting ally comes on the scene. In fact, you can convey your knowledge to your ally and grant your pal a saving throw bonus (see Pointing Out Illusions in Part Three).
The rules don't say what happens if you successfully disbelieve a figment or glamer that doesn't have a visual element. It's a safe bet, however, that you remain aware of the figment or glamer without being affected or hindered in any way.
We're out of time for this week. Next week, we'll complete our study of saving throws against illusion spells beginning with a discussion of what it means to "interact" with an illusion.
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.