Illusions and Disbelief

[Wolffenjugend]

Can a character disbelieve Invisibility or Mirror Image, since they are both illusions? I've read the PH and it seems rather unclear. Can only certain types of illusions be disbelieved? Sources?

Thanks.

 

[Lord Pendragon]

If you mean, can a PC say, "I attempt to disbelieve the invisibility!" then no, Illusions cannot be disbelieved. However, when an illusion allows a saving throw, succeeding at the saving throw is considered "disbelief" in that the illusion does not fool the target. Also, for figments and phantasms, interacting with the object can allow another saving throw, even if a previous one was failed.

For illusions that do not allow saving throws (such as Invisibility,) no you cannot "disbelieve." The definitions of the various types of illusion (pg 158 PH) and what they actually do should explain why.

 

[Elder-Basilisk]

My understanding is that phantasms dissappear if they're disbeleived. Shadow spells have reduced effects. And figments don't effect you negatively at all (but you still can't see through them). Thus illusionary (figment) fog is just as effective as the real thing (maybe more effective since it can't be burned or blown away). Similarly, people pretty much automatically disbelieve things like Mirror Image and Improved Invisibility. But that doesn't actually help them see their target.

 

[Wolffenjugend]

Phantasms don't disappear: "a successful save against an illusion reveals it to be false, but a figment or phantasm remains as a translucent outline."

Also: "Creatures encountering an illusion effect usually do not receive saving throws to recognize it as illusory until they study it carefully or interact with it in some fashion."

To answer my own question, I think, a "disbelief" save is not entitled unless the spell description indicates otherwise. Mirror Image does not have a save listing so my guess is that it is not allowed. Invisibility has a save listing but it seems to be for unwilling recipients of the spell.

HOWEVER...

What I don't understand is why someone who knows an illusion is an illusion (i.e. Mirror Image) cannot spend a round studying it carefully to reveal the "truth." For example, if a round is spent studying Mirror Images then why isn't someone allowed a save to see the illusions for what they are (in this case, translucent outlines of mirror images b/c the spell is a figment). Why is an illusion of mirror images treated differently than an illusion of a fire-breathing dragon (i.e. Silent Spell would allow a save once it is interacted with).

 

[AuraSeer]

Why is an illusion of mirror images treated differently than an illusion of a fire-breathing dragon.

The real answer? That's just how the game works.

The "standard" illusions-- silent image and its brethren-- are very flexible. They can scare, mislead, lure, confuse, and otherwise mess with the minds of enemies. They have to grant saves, for reasons of game balance if nothing else; if they didn't, they would allow foolproof manipulation of enemies, which is plainly overpowered.

By contrast, mirror image is a purely defensive spell. In D&D, defense effects almost never allow a saving throw; you can't make a save to ignore displacement or mage armor or anything like that. Since MI effectively grants a miss chance in combat-- similar to displacement-- there's really no balance reason for it to allow a save.

If the designers wanted absolute, 100% perfect internal consistency, they probably wouldn't call mirror image a figment. Maybe it'd be its own, separate subtype of the Illusion school. It wouldn't matter much anyway. When the general description of a spell type (figments) contradicts the specific description of a given spell (Saving Throw: None), the specific description always wins.