- The sphere allows a Reflex save, but it also has a diameter of 1 foot per level. If I'm 20th level and cast this on a creature, it would have to go 10 feet to one side (2 squares) in order to escape the sphere. If my target's Reflex save is successful, where exactly does it go? Does it jump to a random side? Does the spell simply fail?
- At a high enough level to catch several squares, can I put multiple creatures in a sphere? If so, do they all get Reflex saves?
- If your target succeeds on the Ref save, the sphere doesn't form in the first place: "Reflex negates", thus the effect (1-foot-diameter/level sphere centered around a creature) cannot be triggered, thus the sphere cannot form.
- Probably, and probably. The spell description is a bit vague, but it seems entirely reasonable that others could be trapped within the sphere (the description suggests this is the case: "The sphere cannot be moved ... by the struggles of those within.") and that those others would get a ref save to dive out of the way.
I advise conferring with the GM about how they would adjudicate such a sphere catching multiple creatures before spending too many resources on it (which may require casting the spell in a mock combat situation with your party).
If you're the GM, decide how it works and be consistent. It's fine if other spells (or other force-effects, even Forcecage) work differently, but make sure that Resilient Sphere always works the same (barring specific situational modifiers, of course).
Were I GMing, I would give non-targets who would be caught a ref save to dive out of the way, in the direction of their choosing (using up movement from their next action); an acrobatics check (or saving by 5+/hitting a nat-20 on the check) would let them end the movement standing, else they'd be prone. Large (or larger) creatures who are partially in the space would get the ref save to choose whether to end up inside or outside of the sphere; failure would put them on whichever side the caster wants them to be on.
- If the potential victim succeeds on the Reflex saving throw against the spell resilient sphere, the spell creates no effect. As an evocation spell—rather than a conjuration (creation) spell—, the spell doesn't affect the surrounding area if the target succeeds on the Reflex saving throw because the spell mentions nothing about the effect if it doesn't trap the potential victim (cf. fireball which, if all creatures within the spell's area succeed on their saving throws and have the special ability evasion, still can start fires).
- The resilient sphere is centered on but a lone creature. Were the spell capable of Pokémoning multiple creatures, the spell would say so (probably mentioning saving throws for each creature beyond the first).
The weirdness of the spell resilient sphere is the effect's diameter, which permits the DM no say No based on the DM's opinion of the potential victim's size, which should've been fixed to something less DM-dependent when Pathfinder adapted the spell from Otiluke's resilient sphere for Dungeons and Dragons 3.5 (cf. here). Of course, the spell is serious legacy spell, dating back to Unearthed Arcana (1985) for Advanced Dungeons and Dragons and still bears much the same language from a spell published 30 years ago:
When this spell is cast, the result is a globe of shimmering force which encapsulates the subject creature—if it is small enough to fit within the diameter of the sphere and it fails to successfully save versus spell. The resilient sphere will contain its subject for as long as its dweomer persists, and it is not subject to damage of any sort except from a rod of cancellation, a wand of negation, or a disintegrate or dispel magic spell. These will cause it to be destroyed without harm to the subject. Nothing can pass through the sphere, inside or out, and the target can breathe normally. The subject may struggle, but all that will occur is a movement of the sphere. The globe can be physically moved either by people outside the globe, or by the struggles of those within. The material components of the spell are a hemispherical piece of diamond (or similar hard, clear gem material) and a matching hemispherical piece of gum Arabic. (57)
The 1985 version's Area of Effect is 1 ft. diameter spehere per level of caster. So, yeah, it might be time to update this spell for real.
The rules don’t indicate anything other than the spell simply being negated on a successful save, so I suppose that’s what happens. The creature actually moving (changing squares) and the spell coming into effect but being empty would require special rules; by default, Reflex negates means that a succssful Reflex save eliminates the spell entirely.
This seems really dumb to me, but that’s what it is.
The spell is always centered around a creature and its description indicates that
A globe of shimmering force encloses a creature
Apparently you cannot enclose more than one creature, even if the size is large enough. How that works, I have no idea, since yes, the sphere can get large enough that it seems like it ought to be able to do so.
The wording on this spell is really bizarre. It seems to be split between two ideas, not sure which one it wants to be: either the spell is specifically an enclosure for a single creature (which must be small enough to fit in a CL-ft. radius sphere), or else the spell creates a CL-ft. radius sphere, inside which a creature (or creatures) could be trapped.
By my reading, the spell seems to mostly be the first; there’s no indication that you can create an empty resilient sphere, and there’s the fact that a Reflex save is supposed to negate the spell entirely. However, the lack of something like it being an “up to CL-ft. radius sphere” or something would seem to imply that you always get the full size, even if that’s way bigger than the trapped creature.
The alternative seems contrary to how the spell is worded (i.e. they are very specific about the sphere trapping a creature consistently throughout the spell). If the effect of the spell was simply to create a sphere, which may or may not have a creature in it, I would have expected very different phrasing, emphasizing the sphere rather than the creature. Instead, there would just be rules for what happens if any creatures happen to be in the sphere (and you would expect a Reflex save to let them dive out of the sphere, not negate it). The way the spell is worded doesn’t really support this. Which is unfortunate, because at least to me it seems much more sensible.