JoshuaZ
2022-07-13, 01:19 PM
I've been playing with GPT-3, one of the new text continuation AIs. I've tried seeing what happened if one gave it prompts for a feat and a description and then let it fill in the rest. I've sometimes given it prerequisites already and asked it to complete the benefits section. The results are uneven at best. It has no sense of balance. It sometimes makes a feat a prerequisite for itself. It sometimes mixes editions of games. (It told me one version of a feat was an update for 4e but it clearly used a mix of 5e and PF mechanics.) But some of them, along with some tweaking for balance and fluff were actually close to balanced enough to share here. I'm also not including here any of the real duds. I had to play around a fair bit asking it to retry some things, and adjusting some of the parameters. And some things were just hopelessly not how mechanics worked. For all these feats I started off the prompt text with the additional words "For Dungeons and Dragons" which seemed to help narrow down the process. (This helped minimize it doing things like talking about tapping cards, colored mana, or other things from other games.) My comments are added in blue.
The One Forest is an idea more than an actual forest. The idea is that all forests in all worlds are fundamentally connected. Mechanically, this is reflected in the following feat:
Initiate of the One Forest
You can connect with some of the magic of the One Forest.
Prerequisites: Able to cast a spell of at least first level. Knowledge(Nature) 2 ranks.
Benefit: You can expend a use of a spell slot of at least first level to cast Commune with Nature as a spell-like ability. You can only ask questions about natural features, such as plants, animals, and weather.
It really seems to like the "Expend resource X to duplicate spell Y" mechanic. I'm uncertain if this is a balanced feat or not. On the one hand, Commune With Nature is a higher level spell, but the ending the system tacked on here looks reasonable. The initial fluff text seemed to help it keep it on theme but we'll see later it is pretty good without even that sort of guidance. I liked this result enough that I tried to do some more along this theme.
Master of the One Forest.
Prerequisites: Able cast a spell of at least fifth level. Knowledge(Nature) 5 ranks. Initiate of the One Forest
Benefit: You can expend a use of a spell slot of at least fifth level to cast Plane Shift as a spell-like ability. You can only transport yourself and up to eight other creatures, all of whom must be touching you. You must all be willing to travel to the same destination. Your starting location must be a forested area and your destination must be a forested area of the plane to you which travel.
I added the last sentence here to the GPT-3 text to keep the theme going and for balance reasons.
Mind of the One Forest [psionic]
Prerequisites: Initiate of the One Forest, Able to cast a spell of at least first level. Knowledge(Nature) 5 ranks. Must have a power point pool.
Benefit: You can use your power points to duplicate the effects of certain spells, with your caster level as your usual caster level.
1 power point: Speak with Plants
3 power points: Pass without Trace
5 power points: Commune with Nature
This one is identical to what GPT-3 wrote. Seems balanced.
Terrain Mage
Prerequisites: Able to cast an arcane spell of at least third level. Initiate of the One Forest. Knowledge(Nature) 5 ranks.
Benefit: Choose one type of natural terrain. You gain a +2 bonus on Spellcraft checks to cast spells with the air, earth, fire, or water descriptor in that type of terrain, and on Knowledge (Nature) checks to identify creatures indigenous to that type of terrain.
In addition, you can expend a spell slot or prepared spell of 1st level or higher to duplicate Summon Nature's Ally of the same level as the spell slot expended.
Tireless Wanderer
Prerequisites: Endurance, Run
Benefit: You no longer suffer the ill effects of running long distances or of over-exertion. You can run and move at full speed without penalty, and can run and move twice your normal speed without penalty for a number of rounds per day equal to your Constitution modifier (minimum 1 round per day). These rounds do not need to be consecutive.
After asking for a completion for Terrain Mage, it gave me this feat free without any additional prompting. I'm not sure it completely makes sense, but A for effort!
The next set were all based on the phrase "Arcanum Hourglass." I wanted to see if given minimal prompting. GPT-3 would get hourglass themed things. And it didn't disappoint.
Arcanum Hourglass
You have learned to use the power of time to your advantage. By studying the flow of time, you have learned to control it to a degree.
Prerequisites: Able to cast an arcane spell of at least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks.
Benefit:
You can use this ability to cast spells more quickly than normal. When you cast a spell of zeroth or first level that has a casting time of one standard action, you can reduce the casting time to a swift action. Such spells are difficult to cast even with your control of time. As a result, when you cast a spell this way, you reduce the spells caster level and save DC by 1.
You can use this ability a number of times per day equal to 3 + your Intelligence modifier.
I originally asked this for a prompt with able to cast an arcane spell of at least second level. And it gave me back similar text but allowing it to apply to any spell level. I think restricting it this way is balanced. Also, the flavor sentence at the beginning it wrote and put in benefit section. I've moved it up to be more consistent with the common formatting. But some part of it clearly recognized that hourglass and flow of time go together, and that that should allow a change in casting time. I also added the penalty to save and caster level to help balance things.
Improved Arcanum Hourglass
Your understanding of the flow of time has grown even further, giving you greater control over it.
Prerequisites: Able to cast an arcane spell of at least fifth level. Arcanum Hourglass, Knowledge(Arcana) 10 ranks, Spellcraft 10 ranks.
Benefit: You can now use this ability to cast spells more quickly than normal. When you cast a spell of zeroth or first level that has a casting time of one standard action, you can reduce the casting time to a free action. When you do so this way, you reduce the spells caster level and save DC by 2. Using this ability takes up 2 daily uses of Arcanum Hourglass.
GPT-3 wanted this feat to have its own pool of daily uses. I did not care for that. hence the last sentence. I suspect this may be messing too much with the action economy even as given.
Extra Arcanum Hourglass Use
Prerequisites: Arcanum Hourglass , Able to cast an arcane spell of at least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks.
Benefit: You gain two additional daily uses of Arcanum Hourglass.
Special: You may take this feat multiple times. Each time you may use this feat two times more daily.
I wrote the above feet completely, without any input for GPT-3 building off of its feats.
Archmage of the Hourglass
Prerequisites: Able to cast an arcane spell of at least seventh level. Arcanum Hourglass, Improved Arcanum Hourglass, Knowledge(Arcana) 15 ranks, Spellcraft 15 ranks.
Benefit: You now have complete mastery over the flow of time. You may apply Arcanum Hourglass and Improved Arcanum Hourglass to spells of higher than first level. For each level above first the spell is, you use up one additional daily use of Arcanum Hourglass
GPT-3 wanted this to apply to all spells or all spells of x level for various x. The last sentence I added to try and balance it out more.
Psion of the Hourglass [psionic]
Your mental strength allows you to further control the flow of time.
Prerequisites: Able to cast an arcane spell of at least fourth level. Arcanum Hourglass, Knowledge(Arcana) 7 ranks, Spellcraft 7 ranks.
Benefit: You add your number of psionic feats to your number of daily uses of Arcanum Hourglass. Also, you may apply Arcanum Hourglass to psionic powers as if they were spells of the same level. If you have either Improved Arcanum Hourglass or Archmage of the Hourglass, you may apply them to powers also.
GPT-3 had a lot of trouble making a good version of this, partially I suspect due to the lack of feats interacting with magic and psionics. There are a few, but not many. Both ideas here (the increased daily usage) and the applying to powers were in versions it had, but neither was written in a way that made much sense. So what have we learned? It can make themes, and it seems good at recognizing conceptually related themes, but actually mechanically using them is tough. We'll see more of this pattern later.
I then tried something different:
Mage of the Jade Lotus
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks.
Benefit: You have mastered the arcane arts through the Jade Lotus Order, and can now cast your spells with more power and subtlety. You gain a +2 bonus on Spellcraft checks, and your spells their save DC against creatures that are vulnerable to effects with that descriptor, such as undead which are specifically vulnerable to light effects.
This is balanced, but it isn't really great. There's nothing about it that screams "Jade Lotus" or related to that. That said, GPT-3 did introduce the "Jade Lotus Order" here, which might be worth expanding on on its own.
Shardbinder Mage
Prerequisites: Able to cast an arcane spell of at least third level. Knowledge(Arcana) 3 ranks.
Benefit:
You have learned how to bind shards of magic to your very will. As a result, you can cast a greater number of spells each day, and your spells are more powerful. You gain one additional spell slot of every level but your highest two levels in any arcane spellcasting class. Additionally, when one of those slots is used to cast a damaging spell
You gain an additional spell slot of each level you can cast. In addition, your spells are more potent. When you cast a spell that deals spell damage, the damage is increased by 1d6 per a level of the spell. If the spell is targeted, this applies only to a single target. If the spell allows multiple independently targeted damaging effects, such as a Magic Missile or Scorching Ray, this only applies to one of the missiles or rays.
GPT wanted one additional spell of every level, and it also wanted the increase to damage to occur with all spells one casts, and didn't have the details about spells like Magic Missile. I think I've toned it down a bit. The line about binding shards of magic is due to GPT-3.
Smokeglass Mage
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks.
Benefit:
Your skill with smoke and mirrors has led you to become a smokeglass mage. By using your knowledge of arcane illusions and your ability to create magical smoke, you can confound and befuddle your opponents.
You gain a +1 bonus on all Bluff and Disguise checks. In addition, you can use your smoke to create illusions. By spending 1 round creating smoke, you can create an illusory creature, object, or effect that lasts for 1 minute. This otherwise duplicates Silent Image but as a spell-like ability.
You also may as a move action to create a thick, black smoke that fills a 20-foot-radius sphere centered on you for 1 minute. The smoke obscures all sight, including darkvision, beyond 5 feet. A creature other than yourself that starts its turn in the smoke must make a Fortitude save or become sickened for 1 round.
This is actually two separate versions of the feat it suggested which I combined into one. Is might be too strong this way. Unclear. But note also that it clearly connected "Smokeglass" with ideas connected to smoke.
Tempest Mage
You can control the weather, summoning forth powerful storms at your command.
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks. Spellcraft 3 ranks.
Benefits:
You can sacrifice a spell slot of prepared spell of at least thrid level. you can create one of the following weather effects:
-Cone of Cold: A blast of frigid air deals 1d6 points of cold damage per level of the spell sacrificed (maximum 10d6) to creatures within a 15 foot cone. Fortitude save halves damage.
-Fog: You create a thick fog that obscures all sight, including darkvision, beyond 5 feet. A creature within 5 feet has concealment (attacks have a 50% miss chance). The fog extends to a radius of 10 feet per a level of the spell slot or spell sacrificed.
-Hail: You summon a storm of hail that does 1d6 points of damage per round to any creature in its area. A reflex save halves damage.
-Lightning: You create a Jolt of electricity that arcs out to strike one target. The jolt deals 1d6 points of electricity damage per level . A Reflex save halves damage.
These are all supernatural abilities, with the save DC determined by the usual save DC of a spell of the level in question would be for you.
It got a bit carried away here and had multiple other options which I had to snip out. Also, its mechanics were really wonky so I had to rewrite a lot of them here to make them sensible. But again, it noticed the "tempest" and got a good theme out of it.
Elven Spellsage
You have learned the methods of the Spellsages who study how to cast specific spells particularly well.
Prerequisites: Must be an elf or half-elf, or must be trained by a Spellsage. Able to cast a spell of at least second level.
Benefit: Your training as a Spellsage has taught you to focus your arcane power in new and potent ways. Choose one spell that you know that is not the highest level spell you can cast. That spell now does not provoke attacks of opportunity when you cast it, and if it allows a save, you increase the save DC by 1. If the spell requires a touch attack or ranged touch attack roll, you get a +2 bonus on the roll.
Special: You may take this feat multiple times. Each time it applies to a different spell.
I had to rewrite parts of Elven Spellsage, but I like the design space area a lot. I also added the sentence about specific spells in the fluff bit after GPT-3 had a feat that applied to only a single spell at a time.
I then went on to see if GPT-3 could do interesting things combining magic and rogues. Most of these did not go well, although it clearly understood that "Sneak Attack" and "Arcane Trickster" are both things it should mention, nothing was really mechanically very interesting. The best I got was the following:
Arcane Infiltrator
Prerequisites: Able to cast an arcane spell of at least second level. Stealth 3 ranks.
Benefit: You gain the ability to use the spells Disguise Self and Invisibility on yourself for a number of rounds per day equal to your caster level. You can choose to use these rounds consecutively or separately.
Let's see what happens if we give it the most stereotypical sort of name for a feat:
Doom Mage
Prerequisites: Able to cast an arcane spell of at least first level.
Benefit: You are adept at using your spells to cause destruction and mayhem. You gain a +1 bonus to damage rolls with arcane spells.
That's actually pretty reasonable! And this is the exact wording almost. However, it wanted to also give an ability to cast a "Doomblast" spell. When I searched for this, I found it was apparently a spell from the Path of Exile videogame. This is not the only example of this; it seems to sometimes take terms or ideas from other fantasy or RPG contexts, even when one has explicitly included "Dungeons and Dragons" or "Pathfinder" in the prompt.
Secrets of the Deep Magic
Prerequisites: Able to cast a spell of at least second level. Knowledge(Arcana) 3 ranks. Spellcraft 3 ranks. Heighten Spell
Benefit: Once daily when you cast a spell that is not of the highest level you can cast in that class, you may treat it as if it were the highest level in that class without using up any additional spell slot. Such a spell cannot have any metamagic modifiers.
Special: You may take this feat multiple times. Each time you may use it one more time daily.
This seems reasonably balanced. I had to add the no metamagic modifiers bit for obvious balance reasons but the rest is essentially GPT-3 itself. But this doesn't feel really "Deep Magic" to me. But if someone has another name for it, it could get renamed to something else. I liked this design space enough that I prompted it for a few similar things. That eventually lead to:
Deep Magic Mastery
Prerequisites: Able to cast a spell of least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks. Heighten Spell. Secrets of the Deep Magic
Benefit: When you apply Secrets of the Deep Magic to a spell, you may also increase its caster level by 1.
Archmage of the Deep Magic
Prerequisites: Able to cast a spell of least fifth level. Knowledge(Arcana) 10 ranks. Spellcraft 10 ranks. Heighten Spell. Secrets of the Deep Magic Deep Magic Mastery
Benefit: When you apply Secrets of the Deep Magic to a a spell you may increase its caster level by an additional 1 (stacking with Deep Magic Mastery) and also increase the save DC by 1.
Deep Magic Psionics [psionic]
Prerequisites: Able to cast a spell of least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks. Heighten Spell. Secrets of the Deep Magic. Able to manifest a psionic power of at least first level.
Benefit: You may apply Secrets of Deep Magic to psionic powers you manifest. When you do so, you may increase their effective level to the highest level spell you can cast or the highest level power you may manifest. When you do so, you may not apply any metapsionics or augments to the power in question. If you have Deep Magic Mastery or Archmage of the Deep Magic, you may apply those feats with such powers, increasing the manifester level accordingly.
Overall conclusion: GPT-3 can definitely do themes. It doesn't really understand mechanics, but it can sometimes give a mechanical thing which can be tweaked into a sensible feat. I haven't tried Prestige Classes or spells. My guess is that anything like a PrC is going to be too difficult for it to do sensibly. I intend to try spells later. In the meantime, any feedback about whether my corrections or updates to things actually were balanced would be good. My guess is that some probably are mechanically missing aspects that are needed, so maybe I shouldn't cast too many aspersions about GPT-3s ability to write sound mechanics.
The One Forest is an idea more than an actual forest. The idea is that all forests in all worlds are fundamentally connected. Mechanically, this is reflected in the following feat:
Initiate of the One Forest
You can connect with some of the magic of the One Forest.
Prerequisites: Able to cast a spell of at least first level. Knowledge(Nature) 2 ranks.
Benefit: You can expend a use of a spell slot of at least first level to cast Commune with Nature as a spell-like ability. You can only ask questions about natural features, such as plants, animals, and weather.
It really seems to like the "Expend resource X to duplicate spell Y" mechanic. I'm uncertain if this is a balanced feat or not. On the one hand, Commune With Nature is a higher level spell, but the ending the system tacked on here looks reasonable. The initial fluff text seemed to help it keep it on theme but we'll see later it is pretty good without even that sort of guidance. I liked this result enough that I tried to do some more along this theme.
Master of the One Forest.
Prerequisites: Able cast a spell of at least fifth level. Knowledge(Nature) 5 ranks. Initiate of the One Forest
Benefit: You can expend a use of a spell slot of at least fifth level to cast Plane Shift as a spell-like ability. You can only transport yourself and up to eight other creatures, all of whom must be touching you. You must all be willing to travel to the same destination. Your starting location must be a forested area and your destination must be a forested area of the plane to you which travel.
I added the last sentence here to the GPT-3 text to keep the theme going and for balance reasons.
Mind of the One Forest [psionic]
Prerequisites: Initiate of the One Forest, Able to cast a spell of at least first level. Knowledge(Nature) 5 ranks. Must have a power point pool.
Benefit: You can use your power points to duplicate the effects of certain spells, with your caster level as your usual caster level.
1 power point: Speak with Plants
3 power points: Pass without Trace
5 power points: Commune with Nature
This one is identical to what GPT-3 wrote. Seems balanced.
Terrain Mage
Prerequisites: Able to cast an arcane spell of at least third level. Initiate of the One Forest. Knowledge(Nature) 5 ranks.
Benefit: Choose one type of natural terrain. You gain a +2 bonus on Spellcraft checks to cast spells with the air, earth, fire, or water descriptor in that type of terrain, and on Knowledge (Nature) checks to identify creatures indigenous to that type of terrain.
In addition, you can expend a spell slot or prepared spell of 1st level or higher to duplicate Summon Nature's Ally of the same level as the spell slot expended.
Tireless Wanderer
Prerequisites: Endurance, Run
Benefit: You no longer suffer the ill effects of running long distances or of over-exertion. You can run and move at full speed without penalty, and can run and move twice your normal speed without penalty for a number of rounds per day equal to your Constitution modifier (minimum 1 round per day). These rounds do not need to be consecutive.
After asking for a completion for Terrain Mage, it gave me this feat free without any additional prompting. I'm not sure it completely makes sense, but A for effort!
The next set were all based on the phrase "Arcanum Hourglass." I wanted to see if given minimal prompting. GPT-3 would get hourglass themed things. And it didn't disappoint.
Arcanum Hourglass
You have learned to use the power of time to your advantage. By studying the flow of time, you have learned to control it to a degree.
Prerequisites: Able to cast an arcane spell of at least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks.
Benefit:
You can use this ability to cast spells more quickly than normal. When you cast a spell of zeroth or first level that has a casting time of one standard action, you can reduce the casting time to a swift action. Such spells are difficult to cast even with your control of time. As a result, when you cast a spell this way, you reduce the spells caster level and save DC by 1.
You can use this ability a number of times per day equal to 3 + your Intelligence modifier.
I originally asked this for a prompt with able to cast an arcane spell of at least second level. And it gave me back similar text but allowing it to apply to any spell level. I think restricting it this way is balanced. Also, the flavor sentence at the beginning it wrote and put in benefit section. I've moved it up to be more consistent with the common formatting. But some part of it clearly recognized that hourglass and flow of time go together, and that that should allow a change in casting time. I also added the penalty to save and caster level to help balance things.
Improved Arcanum Hourglass
Your understanding of the flow of time has grown even further, giving you greater control over it.
Prerequisites: Able to cast an arcane spell of at least fifth level. Arcanum Hourglass, Knowledge(Arcana) 10 ranks, Spellcraft 10 ranks.
Benefit: You can now use this ability to cast spells more quickly than normal. When you cast a spell of zeroth or first level that has a casting time of one standard action, you can reduce the casting time to a free action. When you do so this way, you reduce the spells caster level and save DC by 2. Using this ability takes up 2 daily uses of Arcanum Hourglass.
GPT-3 wanted this feat to have its own pool of daily uses. I did not care for that. hence the last sentence. I suspect this may be messing too much with the action economy even as given.
Extra Arcanum Hourglass Use
Prerequisites: Arcanum Hourglass , Able to cast an arcane spell of at least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks.
Benefit: You gain two additional daily uses of Arcanum Hourglass.
Special: You may take this feat multiple times. Each time you may use this feat two times more daily.
I wrote the above feet completely, without any input for GPT-3 building off of its feats.
Archmage of the Hourglass
Prerequisites: Able to cast an arcane spell of at least seventh level. Arcanum Hourglass, Improved Arcanum Hourglass, Knowledge(Arcana) 15 ranks, Spellcraft 15 ranks.
Benefit: You now have complete mastery over the flow of time. You may apply Arcanum Hourglass and Improved Arcanum Hourglass to spells of higher than first level. For each level above first the spell is, you use up one additional daily use of Arcanum Hourglass
GPT-3 wanted this to apply to all spells or all spells of x level for various x. The last sentence I added to try and balance it out more.
Psion of the Hourglass [psionic]
Your mental strength allows you to further control the flow of time.
Prerequisites: Able to cast an arcane spell of at least fourth level. Arcanum Hourglass, Knowledge(Arcana) 7 ranks, Spellcraft 7 ranks.
Benefit: You add your number of psionic feats to your number of daily uses of Arcanum Hourglass. Also, you may apply Arcanum Hourglass to psionic powers as if they were spells of the same level. If you have either Improved Arcanum Hourglass or Archmage of the Hourglass, you may apply them to powers also.
GPT-3 had a lot of trouble making a good version of this, partially I suspect due to the lack of feats interacting with magic and psionics. There are a few, but not many. Both ideas here (the increased daily usage) and the applying to powers were in versions it had, but neither was written in a way that made much sense. So what have we learned? It can make themes, and it seems good at recognizing conceptually related themes, but actually mechanically using them is tough. We'll see more of this pattern later.
I then tried something different:
Mage of the Jade Lotus
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks.
Benefit: You have mastered the arcane arts through the Jade Lotus Order, and can now cast your spells with more power and subtlety. You gain a +2 bonus on Spellcraft checks, and your spells their save DC against creatures that are vulnerable to effects with that descriptor, such as undead which are specifically vulnerable to light effects.
This is balanced, but it isn't really great. There's nothing about it that screams "Jade Lotus" or related to that. That said, GPT-3 did introduce the "Jade Lotus Order" here, which might be worth expanding on on its own.
Shardbinder Mage
Prerequisites: Able to cast an arcane spell of at least third level. Knowledge(Arcana) 3 ranks.
Benefit:
You have learned how to bind shards of magic to your very will. As a result, you can cast a greater number of spells each day, and your spells are more powerful. You gain one additional spell slot of every level but your highest two levels in any arcane spellcasting class. Additionally, when one of those slots is used to cast a damaging spell
You gain an additional spell slot of each level you can cast. In addition, your spells are more potent. When you cast a spell that deals spell damage, the damage is increased by 1d6 per a level of the spell. If the spell is targeted, this applies only to a single target. If the spell allows multiple independently targeted damaging effects, such as a Magic Missile or Scorching Ray, this only applies to one of the missiles or rays.
GPT wanted one additional spell of every level, and it also wanted the increase to damage to occur with all spells one casts, and didn't have the details about spells like Magic Missile. I think I've toned it down a bit. The line about binding shards of magic is due to GPT-3.
Smokeglass Mage
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks.
Benefit:
Your skill with smoke and mirrors has led you to become a smokeglass mage. By using your knowledge of arcane illusions and your ability to create magical smoke, you can confound and befuddle your opponents.
You gain a +1 bonus on all Bluff and Disguise checks. In addition, you can use your smoke to create illusions. By spending 1 round creating smoke, you can create an illusory creature, object, or effect that lasts for 1 minute. This otherwise duplicates Silent Image but as a spell-like ability.
You also may as a move action to create a thick, black smoke that fills a 20-foot-radius sphere centered on you for 1 minute. The smoke obscures all sight, including darkvision, beyond 5 feet. A creature other than yourself that starts its turn in the smoke must make a Fortitude save or become sickened for 1 round.
This is actually two separate versions of the feat it suggested which I combined into one. Is might be too strong this way. Unclear. But note also that it clearly connected "Smokeglass" with ideas connected to smoke.
Tempest Mage
You can control the weather, summoning forth powerful storms at your command.
Prerequisites: Able to cast an arcane spell of at least second level. Knowledge(Arcana) 3 ranks. Spellcraft 3 ranks.
Benefits:
You can sacrifice a spell slot of prepared spell of at least thrid level. you can create one of the following weather effects:
-Cone of Cold: A blast of frigid air deals 1d6 points of cold damage per level of the spell sacrificed (maximum 10d6) to creatures within a 15 foot cone. Fortitude save halves damage.
-Fog: You create a thick fog that obscures all sight, including darkvision, beyond 5 feet. A creature within 5 feet has concealment (attacks have a 50% miss chance). The fog extends to a radius of 10 feet per a level of the spell slot or spell sacrificed.
-Hail: You summon a storm of hail that does 1d6 points of damage per round to any creature in its area. A reflex save halves damage.
-Lightning: You create a Jolt of electricity that arcs out to strike one target. The jolt deals 1d6 points of electricity damage per level . A Reflex save halves damage.
These are all supernatural abilities, with the save DC determined by the usual save DC of a spell of the level in question would be for you.
It got a bit carried away here and had multiple other options which I had to snip out. Also, its mechanics were really wonky so I had to rewrite a lot of them here to make them sensible. But again, it noticed the "tempest" and got a good theme out of it.
Elven Spellsage
You have learned the methods of the Spellsages who study how to cast specific spells particularly well.
Prerequisites: Must be an elf or half-elf, or must be trained by a Spellsage. Able to cast a spell of at least second level.
Benefit: Your training as a Spellsage has taught you to focus your arcane power in new and potent ways. Choose one spell that you know that is not the highest level spell you can cast. That spell now does not provoke attacks of opportunity when you cast it, and if it allows a save, you increase the save DC by 1. If the spell requires a touch attack or ranged touch attack roll, you get a +2 bonus on the roll.
Special: You may take this feat multiple times. Each time it applies to a different spell.
I had to rewrite parts of Elven Spellsage, but I like the design space area a lot. I also added the sentence about specific spells in the fluff bit after GPT-3 had a feat that applied to only a single spell at a time.
I then went on to see if GPT-3 could do interesting things combining magic and rogues. Most of these did not go well, although it clearly understood that "Sneak Attack" and "Arcane Trickster" are both things it should mention, nothing was really mechanically very interesting. The best I got was the following:
Arcane Infiltrator
Prerequisites: Able to cast an arcane spell of at least second level. Stealth 3 ranks.
Benefit: You gain the ability to use the spells Disguise Self and Invisibility on yourself for a number of rounds per day equal to your caster level. You can choose to use these rounds consecutively or separately.
Let's see what happens if we give it the most stereotypical sort of name for a feat:
Doom Mage
Prerequisites: Able to cast an arcane spell of at least first level.
Benefit: You are adept at using your spells to cause destruction and mayhem. You gain a +1 bonus to damage rolls with arcane spells.
That's actually pretty reasonable! And this is the exact wording almost. However, it wanted to also give an ability to cast a "Doomblast" spell. When I searched for this, I found it was apparently a spell from the Path of Exile videogame. This is not the only example of this; it seems to sometimes take terms or ideas from other fantasy or RPG contexts, even when one has explicitly included "Dungeons and Dragons" or "Pathfinder" in the prompt.
Secrets of the Deep Magic
Prerequisites: Able to cast a spell of at least second level. Knowledge(Arcana) 3 ranks. Spellcraft 3 ranks. Heighten Spell
Benefit: Once daily when you cast a spell that is not of the highest level you can cast in that class, you may treat it as if it were the highest level in that class without using up any additional spell slot. Such a spell cannot have any metamagic modifiers.
Special: You may take this feat multiple times. Each time you may use it one more time daily.
This seems reasonably balanced. I had to add the no metamagic modifiers bit for obvious balance reasons but the rest is essentially GPT-3 itself. But this doesn't feel really "Deep Magic" to me. But if someone has another name for it, it could get renamed to something else. I liked this design space enough that I prompted it for a few similar things. That eventually lead to:
Deep Magic Mastery
Prerequisites: Able to cast a spell of least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks. Heighten Spell. Secrets of the Deep Magic
Benefit: When you apply Secrets of the Deep Magic to a spell, you may also increase its caster level by 1.
Archmage of the Deep Magic
Prerequisites: Able to cast a spell of least fifth level. Knowledge(Arcana) 10 ranks. Spellcraft 10 ranks. Heighten Spell. Secrets of the Deep Magic Deep Magic Mastery
Benefit: When you apply Secrets of the Deep Magic to a a spell you may increase its caster level by an additional 1 (stacking with Deep Magic Mastery) and also increase the save DC by 1.
Deep Magic Psionics [psionic]
Prerequisites: Able to cast a spell of least third level. Knowledge(Arcana) 5 ranks. Spellcraft 5 ranks. Heighten Spell. Secrets of the Deep Magic. Able to manifest a psionic power of at least first level.
Benefit: You may apply Secrets of Deep Magic to psionic powers you manifest. When you do so, you may increase their effective level to the highest level spell you can cast or the highest level power you may manifest. When you do so, you may not apply any metapsionics or augments to the power in question. If you have Deep Magic Mastery or Archmage of the Deep Magic, you may apply those feats with such powers, increasing the manifester level accordingly.
Overall conclusion: GPT-3 can definitely do themes. It doesn't really understand mechanics, but it can sometimes give a mechanical thing which can be tweaked into a sensible feat. I haven't tried Prestige Classes or spells. My guess is that anything like a PrC is going to be too difficult for it to do sensibly. I intend to try spells later. In the meantime, any feedback about whether my corrections or updates to things actually were balanced would be good. My guess is that some probably are mechanically missing aspects that are needed, so maybe I shouldn't cast too many aspersions about GPT-3s ability to write sound mechanics.