| Letric |
I really like this spell, but I'm not sure how they work in combat.
Let's say I have an ally who is tripped and next to an enemy. Initiative order is Me>Ally>Enemy.
According to my understanding of the rules, once I cast Silence Image (let's say I cast a wall between them) no one gets a Saving throw unless:
- study it carefully > we can assumed Move Action, otherwise it would be OP
- walks through it or touches it and notices it's not real
- decides to attack through it > so, let's say this action is taken, because maybe the creature is strong enough and thinks it can break it. How do you rule this? Does the creature have blindness for 1 attack until the figment becomes transparent?
Next, my ally: since the enemy never got a Saving Throw, could he just get up and walk to a safe location without any repercussion?
Was there ever a clarification from Paizo that I could show to my DM?
I'm asking because against someone that could Full attack I could potentially trap them in a Maze and they would have to waste 1 move action to touch the Wall and notice it's not real disbelieving it automatically, but if I put a wall in between (at range for example) the only option they have is to waste a Move Action to get a Save and possibly fail at it.
Also, how can I shape it? It's the minimum 10 ft cube or I could make it smaller?
| SlimGauge |
The creature does not have blindness, but cannot see beyond the illusion.
If the creature elects to attack the illusion, he still has to roll an attack (possibly fumbling if those rules are in use). This interaction would get him a save for interacting. A figment's AC is equal to 10 + its size modifier.
Unless you have somehow communicated to your ally what you're doing or he had some way of figuring it out on his own (maybe he spell-crafted your spell as you were casting it), he doesn't automatically know it's an illusion either.
| Letric |
The creature does not have blindness, but cannot see beyond the illusion.
If the creature elects to attack the illusion, he still has to roll an attack (possibly fumbling if those rules are in use). This interaction would get him a save for interacting. A figment's AC is equal to 10 + its size modifier.Unless you have somehow communicated to your ally what you're doing or he had some way of figuring it out on his own (maybe he spell-crafted your spell as you were casting it), he doesn't automatically know it's an illusion either.
So if the creature chooses to attack, what is the Size of a Silent Image Wall? And if it "hits" the wall, doesn't that count as an automatic success? From SRD a character faced with proof that an illusion isn't real needs no saving throw."
My plan is to have Message on and communicate to him that the wall I'm creating is fake. That would give him a +4 to Save, but it could be overheard by enemies with DC 25.
So the enemy has to either:
- hit the wall as standard action > if hit, automatic disbelief
- study it as move action > grants a saving throw
If my ally FAILS the save, and the enemy SUCCEED, does that mean that my ally would be flat footed on the first attack from the enemy?
I'm guessing once you see an arm coming through a wall it counts as Automatic Disbelief
| SlimGauge |
The size is whatever size you made the illusion. If you only made the illusion of a small rock to hide behind, then it's size small. If you made the illusion of a medium-sized rock, then it's medium sized. If you made the illusion large-sized, it extends beyond the boundaries of a single square and is large sized.
If the enemy has multiple attacks (from a high BAB or from TWF or because he has multiple natural attacks), he could attack the wall with his first attack (thus getting at least a save and possibly an automatic disbelieve depending on the exact nature of the attack) and (if the illusion is disbelieved) attack a creature on the other side of the wall with any remaining attacks.
If your ally has already acted in combat, he will not be flat-footed in any case.
| Malignor |
Any time a creature uses an action which interacts with the figment, they can make that save to disbelieve.
The whole power of figments is to cause enemies to misuse or lose actions, via bad sensory information. But their power is only as effective as the belief of the observer.
As for the size, look at the volume restrictions of the spell. That's how much space the caster can work with; any size within that volume is fair game.
| Letric |
The size is whatever size you made the illusion. If you only made the illusion of a small rock to hide behind, then it's size small. If you made the illusion of a medium-sized rock, then it's medium sized. If you made the illusion large-sized, it extends beyond the boundaries of a single square and is large sized.
If the enemy has multiple attacks (from a high BAB or from TWF or because he has multiple natural attacks), he could attack the wall with his first attack (thus getting at least a save and possibly an automatic disbelieve depending on the exact nature of the attack) and (if the illusion is disbelieved) attack a creature on the other side of the wall with any remaining attacks.
If your ally has already acted in combat, he will not be flat-footed in any case.
I see, makes sense. Thanks! I guess if it's something far from you the wasting an action part is pretty good.
I could use this to hide myself behind a wall and still cast spells. If something magical goes though the Wall it doesn't mean it's not real. They would still have to waste a Move Action to analyze it and that doesn't mean they succeed.Regarding my ally, it was the following:
I cast Silent Image to create wall, and I tell my ally it's fake.
He fails the save even with a +4.
Enemy attacks, let's say it has 2 attacks. He notices wall is fake and now it's translucent so it can see my ally, but RAW my ally can't see the enemy.
How could my ally be prepared to that attack if he can't see the enemy?
Once the blade goes through, he can clearly notice the wall is fake, plus I told him so, but up to the point, having failed the save, the wall is real to him.
Ascalaphus
|
If you have proof it's not real, you don't need a saving throw.
If you don't need a saving throw, you don't have to spend actions to gain a saving throw.
If a (regular, not incorporeal) monster's claws pass through the wall at your head with no interference, that would be reasonable proof that the wall isn't real.
Imagine:
Wizard casts Silent Image of a wall. Tells prone fighter via Message that it's fake but Fighter is a moron and fails his save.
Monster can't see fighter. Fighter uses the opportunity to get up from the ground without the monster gaining an AoO. Still can't see the monster; it's like one of those optical illusions where some people just don't get it.
Monster slashes through the wall. As the claw passes through the wall and the graphical glitches resolve themselves, the fighter finally disbelieves the wall. "Now I see it!" *clawtoface*
| Letric |
I'd give the fighter another save for the creature attacking through the fake wall. But not an automatic save unless he tried to attack through it.
It's what I hate about illusion.
When I used this in Runelords, my DM made the enemy roll Save without doing anything, it passed it and it was useless, but my Fighter didn't.
I'm trying to study the rules and get a grasp of them so I can have some argument before using Illusion spell and prep my DM, so I don't start an argument during combat.
I usually remind him of things like "do they have Precise Shot? otherwise it's another -4 to hit" but discussing things like Illusions mid combat is a big no no, I just accept what the DM rules.
If I can come to an agreement before the game, I can use Illusions and know what to expect without getting frustrated.
Ascalaphus
|
It could be an incorporeal creature slashing through the wall.
It would depend on the situation. If we're talking a fighter getting knocked down the stairs by an owlbear, and then this happening - nah, I'm not buying the owlbear suddenly became incorporeal.
If you just met the monster, the GM shows you a picture, and you're looking at it and have no idea what that is, that would be different.
| Tarantula |
Illusions are tough. The casting wizard knows its an illusion, so they're good for him to use, but teammates don't automatically make the save. And you need the save to be high enough to reliably work on the monsters, which means even less likely for the team to make it.
Something that could work better in the future, would be to put the wall in the fighters space. If the monster failed, then the fighter would have concealment, and could move away without getting attacked. If the monster succeeded, it can still see the fighter.
The fighter, I would argue gets an automatic disbelieve, as he sees himself inside of a wall he can move freely through.
| Letric |
Illusions are tough. The casting wizard knows its an illusion, so they're good for him to use, but teammates don't automatically make the save. And you need the save to be high enough to reliably work on the monsters, which means even less likely for the team to make it.
Something that could work better in the future, would be to put the wall in the fighters space. If the monster failed, then the fighter would have concealment, and could move away without getting attacked. If the monster succeeded, it can still see the fighter.
The fighter, I would argue gets an automatic disbelieve, as he sees himself inside of a wall he can move freely through.
Tarantula, that's actually a great idea. A fighter gets insta save while the enemy my belief that something came up in front of him!
| Yorien |
Tarantula, that's actually a great idea. A fighter gets insta save while the enemy my belief that something came up in front of him!
In your particular "wall scenario" a good option I like to use when illusions make creatures almost immediately "interact" with them is to grant creatures perception rolls instead to immediately notice something is amiss. Your fighter might notice his leg suddenly stuck under a "brick wall" can be freely moved, granting him the 100% disbelief... but the enemy, who was watching the fallen fighter the entire time planning to chop him in half might also notice an expected-to-be-stuck-leg to slip "through" a recently appearing "brick wall".
Illusions are more complicated than that.
1-. Illusions mainly affect three senses, SIGHT, HEARING and SMELL. some illusions partially affect TOUCH, by becoming semi-solid, or applying some specific sensations like temperature. Still, TOUCH sense is the main weakness of most illusions and the main way to "catch them".
2-. Disbelieving is not as simple as it sounds. Every illusion is different and is played on a completely different context, there's not a "rule-that-fits-all-scenarios (this is why they're nerfed game after game). An illusion can be soo good that can perfectly deny rolls even while interacting with it. You must thing every specific scenario separately.
3-. "Study an illusion" is not a move action, it can take as low as a free action, or require days or months. Remember that illusions can be changed and may react to specific conditions. As long as the reaction fits the illusion and the creature studying the illusion doesn't notice anything strange, the creature may still be denied the disbelief roll. "Studying" means you are trying to notice something amiss. if you don't notice anything, the illusion stays there while you dance forever around it, and same happens while "interacting" with an illusion. If the illusion reacts in an expected way, you may still be denied the disbelief.
4-. To understand when a creature gets a disbelief roll or automatically disbelieves because the interaction or study is clearly wrong, you must put yourself in place of the creature, the moment the creature would say "WTF?" as a result from one of her actions against the illusion is when she gets the disbelief roll, or automatically disbelieves.
5-. As for players interacting with illusions, a great course of action is to always roleplay the illusion as something real, only that if the illusion interacts in a strange way, casually hint it as part of the conversation or description (try to avoid the typical "make a perception check" as much as possible). If a player grows suspicious and points it, take notice in case a disbelief might be needed, if players ignore the hints... then there's no illusion.
To make a quick example, lets say you create an illusion of a ghost. A child who knows the usual "ghost lore" ("they are scary", "they booo!", "you can pass through them"), actually expects the ghost to be incorporeal and her hand or body to freely pass through the "ghost". On the other side, a player who has already fought or studied ghosts and has more knowledge about them, might quickly notice something doesn't add up (the "ghost" goes through the player, and suddenly... "uhhh... no damage? no corrupting touch?" - WTF moment -).
In the first scenario, lack of knowledge may actually keep the child interacting with the illusion for months or years, "because it's a ghost, and ghosts do that, but don't worry, it's a friendly ghost, I call him Casper"; on the second scenario, the moment the ghost doesn't apply the corrupting touch might hint the player she's not facing a "normal" ghost. If the player points that or grows suspicious, then it might be a good moment to roll that disbelief roll.
Can you create a duplicate image of yourself using silent image, such as a distraction to appear as if you're splitting into two directions or enlarging yourself to a massive size?
The splitting should be possible, but per RAW you no longer can enlarge yourself. Silent Image is a figment, which is one of many words used now to describe illusions that actually means "I've been nerfed from previous games".
...
Figments cannot make something seem to be something else
...
Essentially, if the illusion is a figment, you can "create" something ("copy" yourself), but cannot "alter" something ("enlarge" yourself).
| Pizza Lord |
Illusions are all different and unique and the very circumstances of their use will always require a judgement call based on what is going on and who is 'perceiving' them.
Let's say I have an ally who is tripped and next to an enemy. Initiative order is Me>Ally>Enemy.
In the specific example of your original question. What happens is:
You cast silent image. An illusion of a wall appears between your ally and the enemy.Your ally stands up, enemy does not get an AoO because he cannot see your Ally. This is probably the most important part that matters. (Ascalaphus pointed this out.) It doesn't matter if the enemy identified that you were casting silent image. It doesn't matter if you said immediately afterwards "This is an illusion of a wall." Whether out loud for everyone to hear or just to the ally and the enemy made a Listen (Perception) check. They would get a +4 when trying to disbelieve it if they wanted or when interacting, but it would still be visible to them and blocking their sight.
If suspecting an illusion, it would be reasonable for the enemy to not spend a move-action trying to disbelieve (assuming it wanted to take multiple attacks) and just swing through the wall to where it saw your ally on its turn. It would also be reasonable to try and 5-foot step through it, possibly diagonally, and then take its attacks, though if it ended up stumbling into your ally's square that would provoke an AoO and waste its step putting it back where it started (though it could now at least target the square where the ally is.)
Assuming the ally hasn't gotten up and moved, in which case the attack will miss, but it will be at a 50% total concealment (and if he misses he doesn't know if it's because the target wasn't there or he just missed.) He would also get another save for interacting with the illusion (at +4 if you said it was an illusion.) If he chose to purposefully move through the wall or pass most of his body through (typically at least his head) that would count as automatic success. Just swinging your arm or weapon through is definitely interacting, but being able to pass items or bodyparts through apparently solid objects (that aren't illusions) is still very possible especially in a world were magic exists so that is far from indicating you are dealing with an illusion rather than just a wall that lets swords pass through.
Similarly, you could have created an image of a creature and had it move past the enemy, potentially provoking an AoO and thus letting your ally stand up safely (barring Combat Reflexes). Of course, the enemy is under no compulsion to take its AoO on your illusion, whether it believes it or not, though obviously it should react reasonably. If your illusion is a goblin or other pest, it might reasonably want to save its AoO to crack your ally's skull when he tries to stand up because he's more dangerous-looking. Obviously the enemy would get a save if he 'hits' the illusion, but the Attack of Opportunity was still used whether he disbelieves or not.
Ascalaphus
|
2-. Disbelieving is not as simple as it sounds. Every illusion is different and is played on a completely different context, there's not a "rule-that-fits-all-scenarios (this is why they're nerfed game after game). An illusion can be soo good that can perfectly deny rolls even while interacting with it. You must thing every specific scenario separately.
3-. "Study an illusion" is not a move action, it can take as low as a free action, or require days or months. Remember that illusions can be changed and may react to specific conditions. As long as the reaction fits the illusion and the creature studying the illusion doesn't notice anything strange, the creature may still be denied the disbelief roll. "Studying" means you are trying to notice something amiss. if you don't notice anything, the illusion stays there while you dance forever around it, and same happens while "interacting" with an illusion. If the illusion reacts in an expected way, you may still be denied the disbelief.
I mostly agree with your post, but these bits you have to be careful with. Ultimate Intrigue tried to narrow down what it takes to "study" or "interact" with an illusion.
You get a saving throw if either of these two things happen:
A) You study the illusion
B) You interact with the illusion.
Now A tends to happen because you're suspicious but perhaps don't want to come close. But B can happen quite easily without you having any suspicion there's an illusion going on. For example, there's an illusory enemy and you attack it. Even if you don't hit you're still interacting with the illusion, and receive a saving throw. (If you hit, you probably obtain "proof". Only so many things are plausible incorporeal enemies.) Or you try to cast a spell at the illusion - interaction. Try to Demoralize it with an Intimidate check as a standard action - interaction.
| Yorien |
I mostly agree with your post, but these bits you have to be careful with. Ultimate Intrigue tried to narrow down what it takes to "study" or "interact" with an illusion.
You get a saving throw if either of these two things happen:
A) You study the illusion
B) You interact with the illusion.Now A tends to happen because you're suspicious but perhaps don't want to come close. But B can happen quite easily without you having any suspicion there's an illusion going on. For example, there's an illusory enemy and you attack it. Even if you don't hit you're still interacting with the illusion, and receive a saving throw. (If you hit, you probably obtain "proof". Only so many things are plausible incorporeal enemies.) Or you try to cast a spell at the illusion - interaction. Try to Demoralize it with an Intimidate check as a standard action - interaction.
Well, there are a miriad of rulebooks, each one piling rule after rule, and changing them. In our campaign, for example, we do not use Ultimate Intrigue, and thus no extra "illusion rules". Groups who play with more books may have to aply extra rules,
"Core" illusion rules are the following:
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.
1-. At first sign, it's never an illusion, but a real thing". Each illusion is diferent, there's no single rule that fits all illusion studying or interaction. Perfection is key here, the more detailed the illusion, the better "coded" it is or the faster the caster (if concentrating on it) can make it react to a specific interaction, the less chances for someone to notice something is wrong.
2-. "Studying the illusion carefully" may mean as few as little as a free action, or even months of study depending on how well done the illusion is. Studying your everyday illusory wall from afar without interacting with it may take forever, unless you someday watch a random rat suddenly "going through" the wall as if it wasn't there. Studying a ghost that appears in front of you might take much less.
3-. About interacting, core doesn't just say "interact", but "interact in some fashion". You may apply that to "any" interaction made, but illusions can also react to interactions and if an illusion can react accordingly to the interaction the GM has to decide if the interaction is enough to allow a disbelief roll or not. The disbelief roll should only be made when the illusion cannot react adequately to a specific interaction.
A good example on illusions that actually ignore disbelief rolls (none of them saying they do) are, for example (Improved) Invisibility (a glamer), Mirror Image (figment) and many other illusions that would be much simpler to deal with in case disbelief rolls were allowed. Special mention to Mirror Image, that is constantly "interacted" with to say the least... and you can be sure as hell that the "interacting" creature, as long as she's intelligent, 100% knows she is fighting a g%~!&$n illusion.
Still, every group may rule this differently.
Ascalaphus
|
Well, there are a miriad of rulebooks, each one piling rule after rule, and changing them. In our campaign, for example, we do not use Ultimate Intrigue, and thus no extra "illusion rules". Groups who play with more books may have to aply extra rules,
Ultimate Intrigue aimed not to add new rules, but to provide better explanations of the existing rules in the Core rulebook.
"Core" illusion rules are the following:Quote: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.1-. At first sign, it's never an illusion, but a real thing". Each illusion is diferent, there's no single rule that fits all illusion studying or interaction. Perfection is key here, the more detailed the illusion, the better "coded" it is or the faster the caster (if concentrating on it) can make it react to a specific interaction, the less chances for someone to notice something is wrong.
We don't really have any clear rules to do this, apart from casters with high casting stats having higher save DCs. There's no rules for how fast a caster can react; most likely, if the caster spent the previous round creating/maintaining the illusion, he can have it react. Whether he reacts appropriately will depend on what the caster knows about the thing he's simulating and the enemy he's trying to fool. If he has an illusion of a shadow demon, and he doesn't know that his enemy has a Ghost Touch weapon, he's likely to cause an unbelievable reaction.
2-. "Studying the illusion carefully" may mean as few as little as a free action, or even months of study depending on how well done the illusion is. Studying your everyday illusory wall from afar without interacting with it may take forever, unless you someday watch a random rat suddenly "going through" the wall as if it wasn't there. Studying a ghost that appears in front of you might take much less.
While the CRB doesn't say explicitly just what you need to do to "study it carefully", UI does:
A creature that spends a move action to carefully study an illusion receives a Will saving throw to disbelieve that illusion, so that is a good benchmark from which to work.
It doesn't come up with Move action out of nowhere; that's the action required to actively look/search/examine something (CRB, Perception).
3-. About interacting, core doesn't just say "interact", but "interact in some fashion". You may apply that to "any" interaction made, but illusions can also react to interactions and if an illusion can react accordingly to the interaction the GM has to decide if the interaction is enough to allow a disbelief roll or not. The disbelief roll should only be made when the illusion cannot react adequately to a specific interaction.
"In some fashion" does mean that just about any interaction triggers a saving throw. And it doesn't say "may trigger a saving throw"; it just does. If you interact with the illusion, you receive a saving throw.
So the question is, when does it count as interaction? Again UI explains the Core Rulebook:
But what does it mean to interact with an illusion? It can’t just mean looking at the illusion, as otherwise there would be no need to make the distinction, but drawing the line can be a bit tricky. Fortunately, the rules can help to define that difference. A creature that spends a move action to carefully study an illusion receives a Will saving throw to disbelieve that illusion, so that is a good benchmark from which to work.
Using that as a basis, interacting generally means spending a move action, standard action, or greater on a character’s part. For example, if there were a major image of an ogre, a character who tried to attack the ogre would receive a saving throw to disbelieve, as would a character who spent 1 minute attempting a Diplomacy check on
the ogre. A character who just traded witty banter with the ogre as a free action would not, nor would a character who simply cast spells on herself or her allies and never directly confronted the illusory ogre.For a glamer, interacting generally works the same as for a figment,
except that the interaction must be limited to something the glamer affects. For instance, grabbing a creature’s ear would be an interaction for a human using disguise self to appear as an elf, but not for someone using a glamer to change his hair color. Similarly, visually studying someone would not grant a save against a glamer that
purely changed her voice.
In all these cases UI isn't making new rules, but clarifying the Core Rules (although by extending the example of a Move action to actively study something).
Even if you want to stick only to the Core Rulebook however, I don't agree with your interpretation that studying should be quite so hard or that a witty caster can deny saving throws for interaction.
You've taken the step from "if the illusion doesn't react appropriately, it fails outright" to "if it does react appropriately, you don't gain a saving throw", and that's not correct.
| Yorien |
...
If he has an illusion of a shadow demon, and he doesn't know that his enemy has a Ghost Touch weapon, he's likely to cause an unbelievable reaction....
Already pointed this with a ghost example and corruption touch. But a creature initially interacting with the illusion with no knowledge about the specific behavior and attacks of the illusionary creature (namely, anyone who has not fought or studied Shadow Demons) may not know that. Other rolls may be involved for that (mainly knowledge skills).
While the CRB doesn't say explicitly just what you need to do to "study it carefully", UI does:
As said, that's an UI's extended ruling, not CRB's. If you don't use UI, you don't have to abide by that rule. Some parties may use it (even if they don't use UI), and other may not.
Main issue is: to study an illusion you must first notice there is something strange. A wall suddenly appearing between two creatures when one was about to beat the other to a pulp the other one is clearly strange, a wall placed decades ago in the middle of a corridor might have seen his share of adventurers passing few ft away while checking the corridor for traps without noticing it.
"In some fashion" does mean that just about any interaction triggers a saving throw. And it doesn't say "may trigger a saving throw"; it just does. If you interact with the illusion, you receive a saving throw.
Again, this is UI's extended ruling, not CRB's. Per those rules, you could perfectly disbelieve an Improved Invisibility, a Mirror Image (you know that ALL but one are illusions) or many others. Since "if you interact with the illusion, you receive a saving throw".
I'd say, most lv3+ arcane casters (if not all of them) will strongly disagree with that ruling.
Every illusion is different, and UI is actually trying to rule them into a "one size fits them all" by giving a "you require a move action to be granted a will disbelief" roll and "interacting triggers a saving throw".
Sometimes a more obscure rule (studying it "carefully", carefully being anywhere from instant to infinite, depending on the exact situation) fits much more than a more specific one ("Move action to study", including that red dragon that's been seen in the mountains so people don't wander there. Now you only need a move action to study it when it appears and a good roll to notice it's an illusion).
Still, as said, every party is different and uses different rules and rulebooks. OP's GM will have to decide the type of illusion ruling they'll abide to.
Ascalaphus
|
Ascalaphus wrote:Already pointed this with a ghost example and corruption touch. But a creature initially interacting with the illusion with no knowledge about the specific behavior and attacks of the illusionary creature (namely, anyone who has not fought or studied Shadow Demons) may not know that. Other rolls may be involved for that (mainly knowledge skills)....
If he has an illusion of a shadow demon, and he doesn't know that his enemy has a Ghost Touch weapon, he's likely to cause an unbelievable reaction....
The attacker is fighting something that looks incorporeal, and knows his sword should be effective against it. The illusionist doesn't know the sword should be effective. While there may be obscure incorporeal or "looks incorporeal" monsters that could shrug off the ghost touch effect, those are so rare that the presumption is against them.
Ascalaphus wrote:While the CRB doesn't say explicitly just what you need to do to "study it carefully", UI does:As said, that's an UI's extended ruling, not CRB's. If you don't use UI, you don't have to abide by that rule. Some parties may use it (even if they don't use UI), and other may not.
Main issue is: to study an illusion you must first notice there is something strange. A wall suddenly appearing between two creatures when one was about to beat the other to a pulp the other one is clearly strange, a wall placed decades ago in the middle of a corridor might have seen his share of adventurers passing few ft away while checking the corridor for traps without noticing it.
Studying starts when someone says "I examine that wall" - doesn't mean he's looking for an illusion, he might be looking for a secret door.
And it takes as long as it takes to use Perception to search for stimuli (a Move action). What's happening with the saving throw is that the student is looking at the wall from different angles, prodding it maybe. He's studying the wall so he gets a saving throw. If he succeeds, he maybe notices a weird graphical glitch just like you see sometimes in a video game, which makes him realize the wall isn't quite real.
Ascalaphus wrote:"In some fashion" does mean that just about any interaction triggers a saving throw. And it doesn't say "may trigger a saving throw"; it just does. If you interact with the illusion, you receive a saving throw.Again, this is UI's extended ruling, not CRB's. Per those rules, you could perfectly disbelieve an Improved Invisibility, a Mirror Image (you know that ALL but one are illusions) or many others. Since "if you interact with the illusion, you receive a saving throw".
I'd say, most lv3+ arcane casters (if not all of them) will strongly disagree with that ruling.
Every illusion is different, and UI is actually trying to rule them into a "one size fits them all" by giving a "you require a move action to be granted a will disbelief" roll and "interacting triggers a saving throw".
Sometimes a more obscure rule (studying it "carefully", carefully being anywhere from instant to infinite, depending on the exact situation) fits much more than a more specific one ("Move action to study", including that red dragon that's been seen in the mountains so people don't wander there. Now you only need a move action to study it when it appears and a good roll to notice it's an illusion).
Still, as said, every party is different and uses different rules and rulebooks. OP's GM will have to decide the type of illusion ruling they'll abide to.
You can't disbelieve Invisibility because it doesn't allow a saving throw to disbelieve it in the spell description. Compare:
Saving Throw Will disbelief (if interacted with)]/quote]
Invisibility wrote:Saving Throw Will negates (harmless) or Will negates (harmless, object)The saving throw on Invisibility is for someone who doesn't want to be made invisible. But disbelief does nothing against it.