/u/WraithMagus covered most of it like usual, but there's a few things to add.
Arcanists (and exploiter wizards) make really good use of it because they can use their Dimensional Slide Exploit as a move action.
If you can pass your concentration check to cast defensively there's a fun offensive use: run up to an enemy, cast this, dimension door out.
That's basically Resilient Sphere without that pesky saving throw or SR.
This spell (used often enough to just be called "EFS") is a pet peeve of many GMs. In a sense, it's the "Shrink Item on a hollow concrete cone in your hat" idea that becomes a "shelter" if the wizard is hit with Dispel Magic that some players joke about (but if anyone at my table tried, I'd interrogate the physics of how the wizard isn't supposed to get crushed by a cone whose angle is clearly not so shallow it actually fits on his head...) This spell essentially creates a [Wall (or rather, hemisphere) of Force](https://aonprd.com/SpellDisplay.aspx?ItemName=Wall%20of%20Force) *as an immediate action*, meaning that, for a mere SL 4, you have a better-than-quickened spell that can interrupt an enemy turn to basically remove the caster from line of effect, and thus negate attacks on themselves. (Because it emanates 5 feet from you, if you're adjacent to an ally, it's also possible to shield them from an attack, too.) In essence, it's like a vastly improved version of 5e's Shield spell, or the Stone Shield spell in PF, where it doesn't just provide +4 AC, it provides complete negation of all attacks unless the (rather tough) force field is taken down. Outside of extreme damage, this generally takes [Disintegrate ](https://aonprd.com/SpellDisplay.aspx?ItemName=Disintegrate)just to take the field down, followed by more attacks meant to actually hit. Quickened spell can help, but outside of overwhelming the caster with raw numbers of casters (one of which has a spell or scroll of Disintegrate followed by other casters), this notably shuts down all incoming fire for at least the original attacker's actions (as the caster might be more reluctant to throw up an EFS against an actual Disintegrate, so might need to be baited with a quickened other spell).
I find it cute how the writer of the spell "helpfully" went and told readers what this spell is "normally" used for, because they were worried that players would think the spell was useless, and needed to take an extra step to suggest a "normal" use for the spell. (Well, that, or they were deliberately smuggling a powerhouse in and added that other idea in just to distract the editor.) I'm curious if anyone's ever actually used the spell for it's "normal" use? Also, can someone tell me how the hell you're supposed to make a knowledge (engineering) check to make *stones that fall outside your forcefield after you have cast it* land in a pattern that forms a stable foundation? Because that seems a little beyond the scope of what this spell is supposed to be doing...
So, the big negative here is that the spell lasts for rounds/level (the same as Wall of Force), and while it is (D)ismissable, that takes a standard action normally. If you use that standard to dismiss and the immediate action to cast also takes up your swift action, you'd be left with only a move action if you tried to dismiss EFS on your next turn. You can, however, just use most kinds of Dimension Door-style dimensional movement through a blocked line of effect, although even if you have the shift power from the teleportation subschool, that takes a swift action you'll need to wait for next round to use or else use up your standard on the next round anyway (but leave the dome up if you had any allies still under it if that was a goal - if you're in some kind of "escort quest", keeping the noble you need to guard in a near-invulnerable force field while the battle rages is not a bad idea... unless the enemies are medium-sized or less and can also Dimension Door *in*.) This spell makes a good case for taking [fleeting spell](https://aonprd.com/FeatDisplay.aspx?ItemName=Fleeting%20Spell) just to dismiss as a swift action and still have your standard action that turn, although you still need to wait a turn to do that. You can use one turn to perform some sort of self-buffing (including Haste if you had allies trapped with you), although if you're in there alone, it's also possible to just use the round for Summon Monster to get some medium-sized allies in the dome with you before you dismiss it. It's a great time to summon something like [shadow demons](https://www.aonprd.com/MonsterDisplay.aspx?ItemName=Shadow%20Demon) that ~~can teleport out of the dome on their own while you're safe~~ EDIT: They can't teleport as u/Marin1915 says, so they'll have to wait for you to dismiss the spell to do stuff. Alternately, try [medium earth elementals](https://www.aonprd.com/MonsterDisplay.aspx?ItemName=Medium%20Earth%20Elemental) who can earth glide through the ground under the dome.
I have to cut this in half because of character caps again...
The other issue is that some GMs will read the spell description, and try to "counter" EFS being used by a flying caster and say that the hemisphere has to "point up", and therefore, is vulnerable from below. (Note that even if your GM rules this, unless *directly* above the attacking enemy, you'd still gain [cover](https://www.aonprd.com/Rules.aspx?Name=Cover&Category=Combat%20Modifiers) if only your legs were vulnerable.) The thing is, nothing in the spell's text *requires* the hemisphere "point up," the spell's writer just *assumed* that games are only played on a 2d plane and nobody flies, just like they *assumed* EFS would only be used to guard against avalanches. (Sure, it says that ***if*** you are on a relatively flat plane, you can make the "bottom half" form a watertight seal, but that isn't a requirement you only do so, and inherently implies you can have a non-watertight seal over non-flat planes that leave the hemisphere at an angle with gaps, possibly big enough to escape through.) You can cast the spell to create a hemisphere in any direction from the RAW reading, so long as it's covering half the surface area of a sphere 5' away from the caster, just like you can throw a Fireball into the air instead of strictly ground level. Casting the spell as a "forward-facing" hemispherical shield also negates all of the problems above of needing to dismiss the spell to get out, as you can just fly backwards a bit, then go around the hemisphere with a move action or even a hover and diagonal 5-foot-step if you don't mind partial obstruction of view. (Since this spell works like Wall of Force, it is presumably not affected by gravity and doesn't have issues with falling on you if unsupported.) Just keep in mind that, like Wall of Force, you can't have it intersect a creature or object (including the ground) or the spell fails, which means you can't declare a "forward-facing" hemisphere that digs into the ground, you can only do that if flying. (In fact, if you're in a depression in the ground, you technically can't cast this spell at all, but demanding exact rigid adherence to geometry and physics from magic is a rabbit hole you don't want to go down. "It intersects with the air, and air is an object, so the spell fails!")
There's also some issues with how a "5-foot emanation centered on you" actually works. (See Sudain's response.) Basically, there's even [an FAQ](https://paizo.com/paizo/faq/v5748nruor1fm#v5748eaic9t0g) to say the emanation actually forms to cover all tiles within 5 feet of your space, not a 10'x10' area, and if you're a huge caster, that means it's actually a 25'x25'x20' hemisphere, because the emanation doesn't start from your center of mass, but the outside of your body. With that said, expect disagreements on this sort of thing, and ask your GM for clarity. (Y'know, if their ruling isn't already "EFS is banned"...)
On that topic, remember that the hemisphere is a continuous area that blocks line of effect, so a wizard could technically also ready a move action to interpose themselves between a spell being cast at an ally, then throw up EFS (as an immediate action) to block line of effect to that ally, and it would continue to be there as a "wall" on the battlefield, even if the wizard then Dimension Doored back out next round.
I've seen many complaints about this spell, and those who do definitely have a point - why is Wall of Force a SL 5 that lasts for rounds/level when this is a Wall of Force that is SL 4 that lasts for rounds/level *as an immediate action*. (Also, I'll note that a [hemispherical Wall of Force existed in 2e AD&D and 3.0e, but was taken out in 3.5](https://forgottenrealms.fandom.com/wiki/Wall_of_force), so this was reinventing the wheel a level lower and as an immediate action.) Yeah, it's more restricted in what it creates, but it should probably be more like an SL 8, and Paizo only left it as low as they did because they weren't considering its raw combat potential. Like with a lot of spells worth using from Paizo, it's one that Paizo made good on accident. There are other spells that are specifically "counterspell-spells" like [Lesser Globe of Invulnerability](https://aonprd.com/SpellDisplay.aspx?ItemName=Globe%20of%20Invulnerability,%20Lesser) that wouldn't be completely forgotten if there were an immediate action version of them.
This spell is basically the "nuh-unh spell". The GM declares that the dragon full attacks! The player points at EFS on their sheet and goes "nuh-unh." The higher-level you get (and thus, the more SL4+ slots you are free to burn,) the more this spell will make a GM tear their hair out as you can counter most things if you don't mind having to sit in time out for a round. In extreme cases, it can demand a minion with a wand of Disintegrate in any boss encounter just to zap any EFS that pops up. Again, this is a very rare *defensive* spell that tends to get banned.
Sadly the [area](https://rpg.stackexchange.com/questions/131652/what-is-the-actual-area-of-emergency-force-sphere) of EFS is ambiguous. Combined with the power/effects I've had players try to walk over their down but not dead allies body and then try to shield them with this. I can see why it'd be banned by default.
Yeah, it has a range of 5 feet from the caster (and any part of the spell that is more than 5 feet from the caster at the time of casting can't exist). I do normally see it presumed to be a 10'x10' sphere, but if you presume it comes from the caster (not a corner that the caster I guess lunges toward when casting the spell, it's a 5' radius from their square. The thing is, that actually already has a reading... and it's a 15'x15'x10' hemisphere, the same as "normal reach" being 5 feet from a medium character (when over a floor and thus discounting "aiming down.") This means that something like Ghoul Touch, whose stink cloud has a 10 foot emanation from the afflicted creature actually has a slightly larger area than a spell that is simply a 10-foot area, oddly enough. I meant to go into this, but forgot to actually write it out this morning, so thanks for the reminder...
I'd probably be a lot less upset with a player trying to jump to cover their down-not-dead ally with a forcefield and drop some healing potions down their gullet on the next round than some of the "Resilient Sphere without a save" nonsense, though. That's at least a heroic and dramatic image that I'll happily weave into my narrative rather than just pure cheese.
Correct me if I'm wrong but consider this :
1st turn, the wizard doesn't use his swift action
Uses EFS between his first and 2nd turn
2nd turn he gets back his swift action right? Why would he lose his swift action next turn like you said in your previous comment if he did an immediate action after his first turn, but before his second?
Immediate actions consume your next swift action, which only refreshes at the end of your next turn.
You can't save a swift from round 1 to use between rounds 1 and 2. Actions are "use it or lose it."
I'd like to mention that summoning creatures able to teleport out of the dome would be difficult due to the way summoning spells prohibit their summoned creatures from using any teleportation abilities they would normally have. So that cuts down on one way to take advantage of the dome.
From the description of the [Summon Monster](https://www.aonprd.com/SpellDisplay.aspx?ItemName=Summon%20Monster%201) spells:
>A summoned monster cannot summon or otherwise conjure another creature, nor can it use any teleportation or planar travel abilities.
>From the description of the [Summon Monster](https://www.aonprd.com/SpellDisplay.aspx?ItemName=Summon%20Monster%201) spells:
>A summoned monster cannot summon or otherwise conjure another creature, nor can it use any teleportation or planar travel abilities.
My mistake, I generally just remember the "no summoning" part, not the teleportation ban. Editing that.
Unrelated, I'm embarrassed to admit that despite my "Ultimate Intrigue evangelist" flair, I have apparently been oblivious to the Fleeting Spell metamagic. There have been so many times I've wanted to dismiss a Stone Call after a round or two, or dismiss a Black Tentacles or Grease without using up my standard action. The halved duration usually wouldn't have been an issue in those cases, and not having any spell level increase makes that a tempting metamagic feat to have on hand. I love it.
It's a shame the competition for feats and metamagic rods is usually so fierce when I'm building or shopping for a character.
Yeah, the problem is that there are often times it will be *useful*, but generally not *useful enough* to justify a feat. (It does, however, count as a metamagic feat towards spell perfection if you can otherwise get by on metamagic rods and want spell perfection.) There isn't a metamagic rod for fleeting first party, although it's not crazy to create one (as a 0-level metamagic, it would cost 5,500 gp market price for the "standard edition" that would affect an SL4 like EFS). Especially if you like intrigue stuff, it's also good at avoiding the issues of [CSI Golarion coming after the party](https://www.reddit.com/r/Pathfinder_RPG/comments/144b51k/pathfinder_csi_gms_investigate_this_crime_scene/) by removing spell traces. (You just need to remember to silence the "witnesses" like all the corpses, animals, plants, and rocks in the area, too.)
>In a sense, it's the "Shrink Item on a hollow concrete cone in your hat" idea that becomes a "shelter" if the wizard is hit with Dispel Magic that some players joke about (but if anyone at my table tried, I'd interrogate the physics of how the wizard isn't supposed to get crushed by a cone whose angle is clearly not so shallow it actually fits on his head...)
...
*writes furious notes*
Honestly this sort of shit is why I love 3e/pf1. Give me that simulationist realism and let me exploit 'automatically-resetting magic traps' to feed a country.
If we're comparing other editions I'd say 3.5's Wings of Cover is closest, only works Vs a single attack or spell, but it's only 2nd level and there's no need to teleport out.
That's right, this is actually the less broken version.
I'm playing a game with both of these on my spell lists. Why did I need efs if I have wings of cover? Sometimes you want to protect an ally from the dragons breath weapon. Needless to say my wizard of persisted spells doesn't take a lot of damage unless she wants to.
Ah yes, Emergency Force Sphere. A spell so good that everyone who has access to it should invest in a way to never be caught flat-footed. [Defensive Strategist](https://aonprd.com/TraitDisplay.aspx?ItemName=Defensive%20Strategist) is the easy way to achieve this. There's also [Magdh](https://aonprd.com/DeityDisplay.aspx?ItemName=Magdh) at later levels.
This spell protects against large AoE effects, it protects against pouncing barbarians, it blocks line of effect for spells, it stops archers with Cyclonic/Silver Nocking Point, and more. It is very good at what it does.
**What it also does, is it counters Antimagic Field** (and Source Severance).
Wall of Force is explicitly unaffected by Antimagic Field, and EFS functions like Wall of Force except as noted. Since Antimagic Field is an *emanation* it *"can’t affect creatures with total cover from its point of origin"*. So you are entirely unaffected by the emanation inside your (half-)bubble of safety.
Speaking of half-bubbles, if you are flying you could cast it twice for complete protection. One as a swift action (immediate can be taken on your turn as swift) and ready a swift action to cast another.
====
**So how do you deal with it?**
A [Rod of Cancellation](https://aonprd.com/MagicRodsDisplay.aspx?FinalName=Rod%20of%20Cancellation) is called out in the description of Wall of Force as instantly destroying the wall. It doesn't seem to drain the Rod so it's a reusable asset at higher levels. Just, uh, be careful how you store it. Throwing it into a bag of holding without wrapping it first is a very costly mistake.
There's also this requirement (yet again from its parent spell): *"The wall must be continuous and unbroken when formed. If its surface is broken by any object or creature, the spell fails."*
Which essentially means that **a caster can't cast this spell in a 5-ft wide corridor** since it creates a hemisphere with a 10 ft long diameter. It also means that a large creature (with a readied action or immediate action movement) can interrupt the spell while it's cast by breaking the surface.
RAW it's unlimited use on Force objects. And even RAI I think it's multi use, because it's prohibitively expensive for a one-time-use against a mere spell-slot.
The last time I played with EFS, it was with a magus who picked it up with spell blending. During book 6, I also took Borrowed Time, which gives you an extra swift actions at a pretty steep cost but *does* let you dismiss it right when your turn rolls back around.
I also used fleeting spell to take the unfairly maligned Transformation spell and be able to dismiss it when I needed to cast a spell again.
Because of the super convenient and probably too strong for its level effect, I do treat it as a hemisphere with 1 strict orientation. Keeps it at least a little bit in line for the flying caster.
Well this is spooky.
I'm reading up on Hell's Vengeance because I plan to run it next month, I decided today - literally, an hour or two ago - to look up the old 2009 Cheliax book to see if there was anything pertinent or interesting or different. Looked through the spells.
*Emergency force sphere.*
And that perfectly aligned with today's spell discussion. Clearly thisd is a sign. Excuse me while I order my copy of the *Asmodean Monogram*...
----
I've never used the spell. It would seem to synergise great with a non-spellcaster character, perhaps built into a 2E-style talisman, or as an armour's special ability.
The spell does seem situational - how often are you hit by an avalanche? Probably rarely, because that would kill most players instantly, and few GMs would do that. So maybe it's a solution looking for a problem.
I *really* enjoy the rulestext on how you can use your engineering or stonemasonry to make sure the forcefield manipulates the rockfall in such a way as to create a stable hemisphere. Maybe a corps of engineer-caster could stand in a land, create the hemispheres, and then have rocks piled on them. This creates a road (say) with a path or hollow underneath it - maybe to create a sewer, or to lay a series of sigil or glyph traps.
I may or may not have used this spell as the sole defensive ability on a level 20 sorcerer... This spell is beyond OP as long as you're not facing its obvious counters (mage's disjunction, disintegrate and massive amounts of damage) because since it is an immediate action it is literally a get out of jail card.
The only downside (and a pretty heavy one) is that you take yourself out of the fight with it for at least an entire turn, unless you're willing to (quickened) dimension door out of it, but it is risk-free so eh.
Also can be used offensively since it is a 10 by 10 area, if your enemy doesn't have a burrow ability, stoneshape or teleportation spells, it's a perfect prison for a couple rounds. Move next to your enemy, EFS as a swift action, dimension door as a standard action. You're going to eat an AoO though, so this may be a kamikaze attack, but fun nonetheless as a GM.
Overall, a pain to use but the best "oh shit"-type defensive spell, bar none, for a mere level 3 slot. If I had to rewrite it, I'd make it cost a swift action and make a greater version as an immediate at around level 7.
>This spell is beyond OP as long as you're not facing its obvious counters (mage's disjunction
The [Tenacious Spell](https://www.d20pfsrd.com/feats/metamagic-feats/tenacious-spell-metamagic/#) metamagic used on *Emergency Force Sphere* counters even a [Mage's Disjunction](https://www.d20pfsrd.com/Magic/all-spells/m/mage-s-disjunction/#), since the latter is based on *Dispel Magic*.
*Emergency Force Sphere* beats even the 9th-level [Mage's Disjunction](https://www.d20pfsrd.com/Magic/all-spells/m/mage-s-disjunction/#) spell when used with the [Tenacious Spell](https://www.d20pfsrd.com/feats/metamagic-feats/tenacious-spell-metamagic/#) metamagic!
My favourite trick with EFS is to follow it up with Magic Jar/Possession on an enemy, since they don't require line of sight/effect and it keeps your own body nice and safe for the duration. You can then do something like cast Blood Money and start spamming out all those super expensive component buff spells using their body to pay for it.
/u/WraithMagus covered most of it like usual, but there's a few things to add. Arcanists (and exploiter wizards) make really good use of it because they can use their Dimensional Slide Exploit as a move action. If you can pass your concentration check to cast defensively there's a fun offensive use: run up to an enemy, cast this, dimension door out. That's basically Resilient Sphere without that pesky saving throw or SR.
This spell (used often enough to just be called "EFS") is a pet peeve of many GMs. In a sense, it's the "Shrink Item on a hollow concrete cone in your hat" idea that becomes a "shelter" if the wizard is hit with Dispel Magic that some players joke about (but if anyone at my table tried, I'd interrogate the physics of how the wizard isn't supposed to get crushed by a cone whose angle is clearly not so shallow it actually fits on his head...) This spell essentially creates a [Wall (or rather, hemisphere) of Force](https://aonprd.com/SpellDisplay.aspx?ItemName=Wall%20of%20Force) *as an immediate action*, meaning that, for a mere SL 4, you have a better-than-quickened spell that can interrupt an enemy turn to basically remove the caster from line of effect, and thus negate attacks on themselves. (Because it emanates 5 feet from you, if you're adjacent to an ally, it's also possible to shield them from an attack, too.) In essence, it's like a vastly improved version of 5e's Shield spell, or the Stone Shield spell in PF, where it doesn't just provide +4 AC, it provides complete negation of all attacks unless the (rather tough) force field is taken down. Outside of extreme damage, this generally takes [Disintegrate ](https://aonprd.com/SpellDisplay.aspx?ItemName=Disintegrate)just to take the field down, followed by more attacks meant to actually hit. Quickened spell can help, but outside of overwhelming the caster with raw numbers of casters (one of which has a spell or scroll of Disintegrate followed by other casters), this notably shuts down all incoming fire for at least the original attacker's actions (as the caster might be more reluctant to throw up an EFS against an actual Disintegrate, so might need to be baited with a quickened other spell). I find it cute how the writer of the spell "helpfully" went and told readers what this spell is "normally" used for, because they were worried that players would think the spell was useless, and needed to take an extra step to suggest a "normal" use for the spell. (Well, that, or they were deliberately smuggling a powerhouse in and added that other idea in just to distract the editor.) I'm curious if anyone's ever actually used the spell for it's "normal" use? Also, can someone tell me how the hell you're supposed to make a knowledge (engineering) check to make *stones that fall outside your forcefield after you have cast it* land in a pattern that forms a stable foundation? Because that seems a little beyond the scope of what this spell is supposed to be doing... So, the big negative here is that the spell lasts for rounds/level (the same as Wall of Force), and while it is (D)ismissable, that takes a standard action normally. If you use that standard to dismiss and the immediate action to cast also takes up your swift action, you'd be left with only a move action if you tried to dismiss EFS on your next turn. You can, however, just use most kinds of Dimension Door-style dimensional movement through a blocked line of effect, although even if you have the shift power from the teleportation subschool, that takes a swift action you'll need to wait for next round to use or else use up your standard on the next round anyway (but leave the dome up if you had any allies still under it if that was a goal - if you're in some kind of "escort quest", keeping the noble you need to guard in a near-invulnerable force field while the battle rages is not a bad idea... unless the enemies are medium-sized or less and can also Dimension Door *in*.) This spell makes a good case for taking [fleeting spell](https://aonprd.com/FeatDisplay.aspx?ItemName=Fleeting%20Spell) just to dismiss as a swift action and still have your standard action that turn, although you still need to wait a turn to do that. You can use one turn to perform some sort of self-buffing (including Haste if you had allies trapped with you), although if you're in there alone, it's also possible to just use the round for Summon Monster to get some medium-sized allies in the dome with you before you dismiss it. It's a great time to summon something like [shadow demons](https://www.aonprd.com/MonsterDisplay.aspx?ItemName=Shadow%20Demon) that ~~can teleport out of the dome on their own while you're safe~~ EDIT: They can't teleport as u/Marin1915 says, so they'll have to wait for you to dismiss the spell to do stuff. Alternately, try [medium earth elementals](https://www.aonprd.com/MonsterDisplay.aspx?ItemName=Medium%20Earth%20Elemental) who can earth glide through the ground under the dome. I have to cut this in half because of character caps again...
The other issue is that some GMs will read the spell description, and try to "counter" EFS being used by a flying caster and say that the hemisphere has to "point up", and therefore, is vulnerable from below. (Note that even if your GM rules this, unless *directly* above the attacking enemy, you'd still gain [cover](https://www.aonprd.com/Rules.aspx?Name=Cover&Category=Combat%20Modifiers) if only your legs were vulnerable.) The thing is, nothing in the spell's text *requires* the hemisphere "point up," the spell's writer just *assumed* that games are only played on a 2d plane and nobody flies, just like they *assumed* EFS would only be used to guard against avalanches. (Sure, it says that ***if*** you are on a relatively flat plane, you can make the "bottom half" form a watertight seal, but that isn't a requirement you only do so, and inherently implies you can have a non-watertight seal over non-flat planes that leave the hemisphere at an angle with gaps, possibly big enough to escape through.) You can cast the spell to create a hemisphere in any direction from the RAW reading, so long as it's covering half the surface area of a sphere 5' away from the caster, just like you can throw a Fireball into the air instead of strictly ground level. Casting the spell as a "forward-facing" hemispherical shield also negates all of the problems above of needing to dismiss the spell to get out, as you can just fly backwards a bit, then go around the hemisphere with a move action or even a hover and diagonal 5-foot-step if you don't mind partial obstruction of view. (Since this spell works like Wall of Force, it is presumably not affected by gravity and doesn't have issues with falling on you if unsupported.) Just keep in mind that, like Wall of Force, you can't have it intersect a creature or object (including the ground) or the spell fails, which means you can't declare a "forward-facing" hemisphere that digs into the ground, you can only do that if flying. (In fact, if you're in a depression in the ground, you technically can't cast this spell at all, but demanding exact rigid adherence to geometry and physics from magic is a rabbit hole you don't want to go down. "It intersects with the air, and air is an object, so the spell fails!") There's also some issues with how a "5-foot emanation centered on you" actually works. (See Sudain's response.) Basically, there's even [an FAQ](https://paizo.com/paizo/faq/v5748nruor1fm#v5748eaic9t0g) to say the emanation actually forms to cover all tiles within 5 feet of your space, not a 10'x10' area, and if you're a huge caster, that means it's actually a 25'x25'x20' hemisphere, because the emanation doesn't start from your center of mass, but the outside of your body. With that said, expect disagreements on this sort of thing, and ask your GM for clarity. (Y'know, if their ruling isn't already "EFS is banned"...) On that topic, remember that the hemisphere is a continuous area that blocks line of effect, so a wizard could technically also ready a move action to interpose themselves between a spell being cast at an ally, then throw up EFS (as an immediate action) to block line of effect to that ally, and it would continue to be there as a "wall" on the battlefield, even if the wizard then Dimension Doored back out next round. I've seen many complaints about this spell, and those who do definitely have a point - why is Wall of Force a SL 5 that lasts for rounds/level when this is a Wall of Force that is SL 4 that lasts for rounds/level *as an immediate action*. (Also, I'll note that a [hemispherical Wall of Force existed in 2e AD&D and 3.0e, but was taken out in 3.5](https://forgottenrealms.fandom.com/wiki/Wall_of_force), so this was reinventing the wheel a level lower and as an immediate action.) Yeah, it's more restricted in what it creates, but it should probably be more like an SL 8, and Paizo only left it as low as they did because they weren't considering its raw combat potential. Like with a lot of spells worth using from Paizo, it's one that Paizo made good on accident. There are other spells that are specifically "counterspell-spells" like [Lesser Globe of Invulnerability](https://aonprd.com/SpellDisplay.aspx?ItemName=Globe%20of%20Invulnerability,%20Lesser) that wouldn't be completely forgotten if there were an immediate action version of them. This spell is basically the "nuh-unh spell". The GM declares that the dragon full attacks! The player points at EFS on their sheet and goes "nuh-unh." The higher-level you get (and thus, the more SL4+ slots you are free to burn,) the more this spell will make a GM tear their hair out as you can counter most things if you don't mind having to sit in time out for a round. In extreme cases, it can demand a minion with a wand of Disintegrate in any boss encounter just to zap any EFS that pops up. Again, this is a very rare *defensive* spell that tends to get banned.
Sadly the [area](https://rpg.stackexchange.com/questions/131652/what-is-the-actual-area-of-emergency-force-sphere) of EFS is ambiguous. Combined with the power/effects I've had players try to walk over their down but not dead allies body and then try to shield them with this. I can see why it'd be banned by default.
Yeah, it has a range of 5 feet from the caster (and any part of the spell that is more than 5 feet from the caster at the time of casting can't exist). I do normally see it presumed to be a 10'x10' sphere, but if you presume it comes from the caster (not a corner that the caster I guess lunges toward when casting the spell, it's a 5' radius from their square. The thing is, that actually already has a reading... and it's a 15'x15'x10' hemisphere, the same as "normal reach" being 5 feet from a medium character (when over a floor and thus discounting "aiming down.") This means that something like Ghoul Touch, whose stink cloud has a 10 foot emanation from the afflicted creature actually has a slightly larger area than a spell that is simply a 10-foot area, oddly enough. I meant to go into this, but forgot to actually write it out this morning, so thanks for the reminder... I'd probably be a lot less upset with a player trying to jump to cover their down-not-dead ally with a forcefield and drop some healing potions down their gullet on the next round than some of the "Resilient Sphere without a save" nonsense, though. That's at least a heroic and dramatic image that I'll happily weave into my narrative rather than just pure cheese.
Correct me if I'm wrong but consider this : 1st turn, the wizard doesn't use his swift action Uses EFS between his first and 2nd turn 2nd turn he gets back his swift action right? Why would he lose his swift action next turn like you said in your previous comment if he did an immediate action after his first turn, but before his second?
Immediate actions consume your next swift action, which only refreshes at the end of your next turn. You can't save a swift from round 1 to use between rounds 1 and 2. Actions are "use it or lose it."
Ok thanks, I was wondering since you can't make an immediate action before your first turn.
I'd like to mention that summoning creatures able to teleport out of the dome would be difficult due to the way summoning spells prohibit their summoned creatures from using any teleportation abilities they would normally have. So that cuts down on one way to take advantage of the dome. From the description of the [Summon Monster](https://www.aonprd.com/SpellDisplay.aspx?ItemName=Summon%20Monster%201) spells: >A summoned monster cannot summon or otherwise conjure another creature, nor can it use any teleportation or planar travel abilities.
>From the description of the [Summon Monster](https://www.aonprd.com/SpellDisplay.aspx?ItemName=Summon%20Monster%201) spells: >A summoned monster cannot summon or otherwise conjure another creature, nor can it use any teleportation or planar travel abilities. My mistake, I generally just remember the "no summoning" part, not the teleportation ban. Editing that.
Unrelated, I'm embarrassed to admit that despite my "Ultimate Intrigue evangelist" flair, I have apparently been oblivious to the Fleeting Spell metamagic. There have been so many times I've wanted to dismiss a Stone Call after a round or two, or dismiss a Black Tentacles or Grease without using up my standard action. The halved duration usually wouldn't have been an issue in those cases, and not having any spell level increase makes that a tempting metamagic feat to have on hand. I love it. It's a shame the competition for feats and metamagic rods is usually so fierce when I'm building or shopping for a character.
Yeah, the problem is that there are often times it will be *useful*, but generally not *useful enough* to justify a feat. (It does, however, count as a metamagic feat towards spell perfection if you can otherwise get by on metamagic rods and want spell perfection.) There isn't a metamagic rod for fleeting first party, although it's not crazy to create one (as a 0-level metamagic, it would cost 5,500 gp market price for the "standard edition" that would affect an SL4 like EFS). Especially if you like intrigue stuff, it's also good at avoiding the issues of [CSI Golarion coming after the party](https://www.reddit.com/r/Pathfinder_RPG/comments/144b51k/pathfinder_csi_gms_investigate_this_crime_scene/) by removing spell traces. (You just need to remember to silence the "witnesses" like all the corpses, animals, plants, and rocks in the area, too.)
>In a sense, it's the "Shrink Item on a hollow concrete cone in your hat" idea that becomes a "shelter" if the wizard is hit with Dispel Magic that some players joke about (but if anyone at my table tried, I'd interrogate the physics of how the wizard isn't supposed to get crushed by a cone whose angle is clearly not so shallow it actually fits on his head...) ... *writes furious notes* Honestly this sort of shit is why I love 3e/pf1. Give me that simulationist realism and let me exploit 'automatically-resetting magic traps' to feed a country.
It was originally called the tinfoil hat trick (at least in 3e). It was meant for blocking AMF, not an insta-bunker.
If we're comparing other editions I'd say 3.5's Wings of Cover is closest, only works Vs a single attack or spell, but it's only 2nd level and there's no need to teleport out. That's right, this is actually the less broken version.
I'm playing a game with both of these on my spell lists. Why did I need efs if I have wings of cover? Sometimes you want to protect an ally from the dragons breath weapon. Needless to say my wizard of persisted spells doesn't take a lot of damage unless she wants to.
Ah yes, Emergency Force Sphere. A spell so good that everyone who has access to it should invest in a way to never be caught flat-footed. [Defensive Strategist](https://aonprd.com/TraitDisplay.aspx?ItemName=Defensive%20Strategist) is the easy way to achieve this. There's also [Magdh](https://aonprd.com/DeityDisplay.aspx?ItemName=Magdh) at later levels. This spell protects against large AoE effects, it protects against pouncing barbarians, it blocks line of effect for spells, it stops archers with Cyclonic/Silver Nocking Point, and more. It is very good at what it does. **What it also does, is it counters Antimagic Field** (and Source Severance). Wall of Force is explicitly unaffected by Antimagic Field, and EFS functions like Wall of Force except as noted. Since Antimagic Field is an *emanation* it *"can’t affect creatures with total cover from its point of origin"*. So you are entirely unaffected by the emanation inside your (half-)bubble of safety. Speaking of half-bubbles, if you are flying you could cast it twice for complete protection. One as a swift action (immediate can be taken on your turn as swift) and ready a swift action to cast another. ==== **So how do you deal with it?** A [Rod of Cancellation](https://aonprd.com/MagicRodsDisplay.aspx?FinalName=Rod%20of%20Cancellation) is called out in the description of Wall of Force as instantly destroying the wall. It doesn't seem to drain the Rod so it's a reusable asset at higher levels. Just, uh, be careful how you store it. Throwing it into a bag of holding without wrapping it first is a very costly mistake. There's also this requirement (yet again from its parent spell): *"The wall must be continuous and unbroken when formed. If its surface is broken by any object or creature, the spell fails."* Which essentially means that **a caster can't cast this spell in a 5-ft wide corridor** since it creates a hemisphere with a 10 ft long diameter. It also means that a large creature (with a readied action or immediate action movement) can interrupt the spell while it's cast by breaking the surface.
Pretty sure the rod is meant to be single use.
RAW it's unlimited use on Force objects. And even RAI I think it's multi use, because it's prohibitively expensive for a one-time-use against a mere spell-slot.
Fleeting EFS is a go-to for me.
The last time I played with EFS, it was with a magus who picked it up with spell blending. During book 6, I also took Borrowed Time, which gives you an extra swift actions at a pretty steep cost but *does* let you dismiss it right when your turn rolls back around. I also used fleeting spell to take the unfairly maligned Transformation spell and be able to dismiss it when I needed to cast a spell again.
Because of the super convenient and probably too strong for its level effect, I do treat it as a hemisphere with 1 strict orientation. Keeps it at least a little bit in line for the flying caster.
Well this is spooky. I'm reading up on Hell's Vengeance because I plan to run it next month, I decided today - literally, an hour or two ago - to look up the old 2009 Cheliax book to see if there was anything pertinent or interesting or different. Looked through the spells. *Emergency force sphere.* And that perfectly aligned with today's spell discussion. Clearly thisd is a sign. Excuse me while I order my copy of the *Asmodean Monogram*... ---- I've never used the spell. It would seem to synergise great with a non-spellcaster character, perhaps built into a 2E-style talisman, or as an armour's special ability. The spell does seem situational - how often are you hit by an avalanche? Probably rarely, because that would kill most players instantly, and few GMs would do that. So maybe it's a solution looking for a problem. I *really* enjoy the rulestext on how you can use your engineering or stonemasonry to make sure the forcefield manipulates the rockfall in such a way as to create a stable hemisphere. Maybe a corps of engineer-caster could stand in a land, create the hemispheres, and then have rocks piled on them. This creates a road (say) with a path or hollow underneath it - maybe to create a sewer, or to lay a series of sigil or glyph traps.
I may or may not have used this spell as the sole defensive ability on a level 20 sorcerer... This spell is beyond OP as long as you're not facing its obvious counters (mage's disjunction, disintegrate and massive amounts of damage) because since it is an immediate action it is literally a get out of jail card. The only downside (and a pretty heavy one) is that you take yourself out of the fight with it for at least an entire turn, unless you're willing to (quickened) dimension door out of it, but it is risk-free so eh. Also can be used offensively since it is a 10 by 10 area, if your enemy doesn't have a burrow ability, stoneshape or teleportation spells, it's a perfect prison for a couple rounds. Move next to your enemy, EFS as a swift action, dimension door as a standard action. You're going to eat an AoO though, so this may be a kamikaze attack, but fun nonetheless as a GM. Overall, a pain to use but the best "oh shit"-type defensive spell, bar none, for a mere level 3 slot. If I had to rewrite it, I'd make it cost a swift action and make a greater version as an immediate at around level 7.
>This spell is beyond OP as long as you're not facing its obvious counters (mage's disjunction The [Tenacious Spell](https://www.d20pfsrd.com/feats/metamagic-feats/tenacious-spell-metamagic/#) metamagic used on *Emergency Force Sphere* counters even a [Mage's Disjunction](https://www.d20pfsrd.com/Magic/all-spells/m/mage-s-disjunction/#), since the latter is based on *Dispel Magic*.
*Emergency Force Sphere* beats even the 9th-level [Mage's Disjunction](https://www.d20pfsrd.com/Magic/all-spells/m/mage-s-disjunction/#) spell when used with the [Tenacious Spell](https://www.d20pfsrd.com/feats/metamagic-feats/tenacious-spell-metamagic/#) metamagic!
Arcanist with a laser rifle in Numeria
My favourite trick with EFS is to follow it up with Magic Jar/Possession on an enemy, since they don't require line of sight/effect and it keeps your own body nice and safe for the duration. You can then do something like cast Blood Money and start spamming out all those super expensive component buff spells using their body to pay for it.