Author Topic: Servant Stat Conversions  (Read 7321 times)

Andoriol

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Servant Stat Conversions
« on: February 19, 2014, 06:57:34 AM »
Because NEEEEEEEERRRRRRRRRRRRRDDDDDDDD

Right, as part of the crossover fanfic I’ve been working on, I’ve struggled to figure out a way to convert Servant stats into something easier to work with as well as equivalents in other universes to ensure that characters stayed within their limits as well as get an idea what they could do.

It ended up being a very rough game system, and because I thought someone else might get some use out of this or at least find it amusing, and hell, any help in fleshing this out would be amazing as well as how to convert other series or systems towards it. I’m going to add more as I figure out how to convert them or codify the conversions I already have.

Conversion Notes:
Spoiler for Hiden:
I’m converting to a significantly modified Pathfinder / D&D system because it A). Has the most detail and granularity of the systems that I’m familiar with and B). The conversion is surprisingly and delightfully easy, though not perfect.

Usually, using the starting health of an NPC or level 1 character with baseline stats to determine lethality, and then determining weapon strength from their damage compared to that baseline health. Core stats seem best determined by starting with the Carrying Capacity and converting between those to get a conversion rate, and then expanding it to the other traits.

Alterantively, one can assume that the maximum, unaugmented level a human can reach as well as the ‘average’, and then compare that to the max stats and base stats of characters, taking into account any magic, Ki, or other things that would allow a person to exceed the normal cap. Then getting a conversion factor based on lining up the base and max levels.

 
Servant Parameter Conversion

Traits:
As a general rule, I’m treating traits as such, remembering that a “+” means that the trait can situationally be increased to up to twice the original rating:

E- = 0 – 9
E = 10 – 19
D = 20 – 29
C = 30 – 39
B = 40 – 49
A = 50 – 59

Strength:
Strength rating is determined as per the Strength Bonus of Dungeons & Dragons 3 / Pathfinder.

This works out surprisingly well when compared to the demonstrated effects of high strength. Remembering that each +1 represents another point of damage for melee attacks and the usual HP and DR of items in the Pathfinder/D&D systems, this reasonably approximates what Servants seem to do with their given Strength Rating and without weapons.

Assuming he wasn’t being Mad Enhanced at the time, during the Graveyard portion of F/SN Berserker vs Archer vs Saber, Berserker has B+ rank strength. Stone has a DR of 8 and 15 hp per inch. That means that smashing through a gravestone would subtract ~25 - 40 from Berserkers strength, bringing it into the realm of Sabers B rank strength. Additionally, using Saber as a missile and assuming equal damage between Saber and the statue, 80 – 100 damage is reasonable to destroy it.

This is also allows F/Z Berserker to punch holes in things like the modern jet to rip things out. Given that iron or steel has a DR of 10 and ~30 HP per inch, even though the fighter jets’ armor would have better DR than that, Berserkers A rank strength of 50 – 59 would still reasonably punch through it even without assuming the damage his hand itself would do (negligible under Pathfinder rules).

Additionally, if a person starts with 18 or 20 Strength, and funnels all of their stat increases into Strength (assuming +2 per stat increase, and a total of 5 stat increases at level 20) they would end up with a bonus of +10, which puts ‘peak human’ at approximately minimum Servant. With ‘Epic’ levels of ~30 bringing someone solidly into E rank.

All in all, this seems like a decent baseline from which to work. Perfect? No. But the Fate series at very least plays a bit loose with the numbers so it’s passable.


Agility:
Working off of the same template as Strength, a +1 for Dexterity represents one point on the Servant scale, with the added caveat that movement speed would be determined by 30 ft per round + (Dexterity Bonus / 2) to represent how higher Agility also represents higher speed, with obvious exceptions of some Servants being faster or slower than their Agility otherwise would indicate, but it’s an approximation.

This one’s much harder to approximate as there aren’t that many exclusively Agility based feats to compare to that I’m aware of. There’s running up walls, but that’s hard to convert to Pathfinder/D&D. So exempting a better way to represent it, I’m going for consistency here.


Endurance:
The Servant’s ‘Health Limit’ (A.K.A. – HP) is equal to their specific Endurance rating. Generally, Servants reduce incoming damage by (Endurance/10). Damage to fill someone’s health limit doesn’t immediately kill them, but is a fatal wound that will bleed out without medical attention. When a person (or Servant) reaches -10, they die. Endurance is calculated as the Pathfinder / D&D Constitution bonus.

This one’s a bit different. It seems to represent how resistant to damage the Servant is as well as how much total damage they can take. Servants, sans armor (or F/SN Berserker) don’t appear to be terribly resistant to damage, just able to take a surprising amount or absurdly skilled to the point of avoiding or mitigating it in the first place to a ridiculous degree.

Since we determine Endurance/Reslience/HP and Strength as contrasts to one another, we’re using the same conversion factor as Strength.


Mana:
One point of the ‘Mana’ stat represents access to ~25 units of Prana, either in the form of internal reserves or access to it through Magic Circuits enabling the usage of Mana, or Divine Words allowing for direct manipulation of Mana at minimal cost of Od.

This one was really hard and I’m still iffy on it. Anyways, B-rank Mana for Saber (under Shirou) means access to 1250 units of Prana with her Dragon Core upon summoning. B rank meaning 40 – 49. This gives us a conversion of ~30 – 25, which sort of matches what Fate says about the average Mangus’ reserves of 25 prana.

But if that were strictly the case, even given a power boost from his contract, F/SN Archer having B-rank Mana is ridiculous if you assume that Mana represents only their internal reserves. Shirou has 27 circuits and would need to hold 38 prana in each circuit to make that possible, which is more than even Rin, a prodigy.

However, if I’m understanding Magic Circuits properly, they store a relatively small amount of prana within them. This is the users Od. Spells are cast using a small amount of the users Od, and use the Circuits capacity to manipulate the surrounding Mana. The amount of Od required to manipulate a given amount of Mana is based on the affinity of the Mangus. The maximum amount of Prana is determined by the quality of the Circuits themselves (Their ‘capacity’, such as Shirou’s circuits holding a maximum of 10 units of Prana each). So it may make more sense that Mana represents the Servant’s effective Prana capacity given both reserves of Od and the conversion of that into Prana for magic.

Figuring out what each unit of prana translates to though, is horrendously difficult. I have been unable to find any serious costs for spells in the Fate universe other than Shirou’s Incarnation modified Od costs.

As a placeholder, the best I can figure is the following as a conversion rate between magics is as follows:

D&D – (Spell Level + 1)^3 * 5. This means that D&D spells would cost as follows:

Spoiler for Hiden:
Cantrips – 5 Prana ; Examples: Light, Detecting Magic, Minor Repairs, Stop Bleeding, Make noise, 5-lb. telekinesis

1st Level – 40 Prana ; Cause fear in one being for ~30 seconds, Comprehend Languages, Heal the equivalent of an E- rank attack, Endure Elements, Weakly enchant a weapon (+1), Weak armor, E- rank touch attacks, change your appearance, small stationary illusions

2nd Level – 135 Prana ; Examples: An E rank touch attack, Weak stat boost for several minutes, Listen to thoughts nearby, create a permanent heatless light, E rank beam attack, Invisibility

3rd Level – 320 Prana ; Examples: Walk on Water, Breathe underwater, Inflict a disease, High E rank touch attack, Melding into stone, Protect against Scrying, Summon a magic horse for 7 hours, Low E Rank attack against a 40 foot diameter or in a long line, Make everyone within 10 ft invisible, Become a human sized or small animal, increase speed significantly

4th Level – 625 Prana ; Examples: Walk on air, Low D rank touch attack, Speak any language, Short range teleport, create simple materials from nothing

5th Level – 1080 Prana ; Examples: Heal a D rank attack restores life to a being slain in the past minute, Heal or inflict an E- rank attack for 9+ people, Restore the recently dead to life, See through all illusions, High D-rank cone of cold, teleport self miles with some error

6th Level – 1715 Prana ; Examples: Summon a barrier of whirling blades around the user that lasts for a minute and inflicts a C rank attack against any that pass through it, C rank lighting that hits 11 targets, moving illusions, travel through shadows, become a dragon the same size as you, A rank beam that disintegrates the target

7th Level – 2560 Prana ; Examples: Control the weather within several miles, Regenerate (heal from a C rank attack, regrow limbs), (truly) Resurrect a dead body, Reflect 7 – 10 spell levels, teleport self miles with no error, A+ rank attack against a single target, Reverse local gravity, Create a small demiplane that lasts for several days.

8th Level – 3645 Prana ; Examples: Antimagic Field (No magic within 10 ft), Cause a 160 ft diameter earthquake, Firestorm (B rank attack against all in an area), become a huge dragon, create a backup clone, Trap a soul in a gem, A rank beam of cold that also reduces Agility, C rank sonic attack against all nearby

9th Level - 5000 Prana ; Examples: Resurrect someone even without a body, Permanently imprison touched subject, A rank fireball or 4 simultaneous C rank fireballs, ‘stop time’ for 10 to 30 seconds

If I could figure out the amount of Prana in an A rank attack (such as Rin’s gems) I could work backwards and figure something out, but as is, this is the best I’ve got. Any suggestions would be delightful.


Luck:
Another tricky stat, mostly because there’s nothing equivalent to it in the majority of game systems. My best approximation is that it allows the user to ‘roll’ their luck to improve/inhibit another effect a number of times per day equal to Luck / 10 (rounded down).


Noble Phantasm:
Just the average of the Noble Phantasms that the Servant/Character has.



Skills: WIP
More than happy to have any suggestions whatsoever on this:

Charisma:
Directly equal to the D&D / Pathfinder Charisma Bonus + Diplomacy rating of the character.

Item Creation:
Directly correlated to the Effective Caster Level of the character when it comes to creating magical items.

Magic Resistance: (WIP)
Likely directly related to Spell Resistance, but acting as additional Damage Resistance vs a spell and/or a bonus to Saves against spells that don’t deal damage.



Noble Phantasms:
Every point of average Pathfinder / D&D damage an attack would do, an armor would stop, or the save DC of an effect equals a point towards the rating of the Noble Phantasm.

Remembering that an A rank Mystic Code is the equivalent to a C rank phantasm, and an A rank is likely the best a human can reasonably make, here’s some approximations:

A powerfully enchanted weapon: 4.5 (Longsword) + 7 (Alignment based damage) + 7 (Elemental Based damage) + 3.5 (Bleed damage) + 5 (Enchantment bonus) = 28

A powerfully enchanted armor set: 9 Full Plate + 5 Enchantment +10 ‘Invulnerable x 2’ = 24

A very powerful spell effect 10 + 9th level + 10 Attribute bonus = 29

This also means that to get the ‘human’ level rankings of these things, you merely double them and compare it to the usual Servant table.


Notes:
Servants consume 6 units of prana per day manifested?

Magi respire/regain ??% of the number of Circuits they have in prana per day?

The natural maximum for the average human in anything tends to be 30. Level 30 in a discipline/class, an attribute of 30, a skill rated at 30, etc, etc. This means that a dedicated, gifted, but unaugmented human can approach C rank in Servant terms in many areas, though even the greatest of humans can only approach D rank in the core parameters.

The 'system' treats armor not as a bonus to not getting hit as Pathfinder / D&D do by default, but rather as Damage Resistance.

The 'system' treats the ability to deflect blows and avoid death that is gained from skill (the classic HP rating) as something seperate from the actual damage a body can take (the Wounds, based on Endurance/Constitution). Based heavily on the alternate Wounds/Vigor system in Pathfinder Ultimate Combat.

How the 'system' rolls dice is not a major concern for me since I'm using this primarily as a guideline for relative character strengths and weaknesses for crossovers and fiction, but it's a fascinating question that I'd love input on.

Cherry Lover

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Re: Servant Stat Conversions
« Reply #1 on: February 20, 2014, 01:07:22 AM »
I'm not sure that there is a direct link between the rank of a spell and the amount of prana used to create it. Certainly Caster can cast spells with a fraction of the prana a modern magus would use to do the same thing. So, given that, I'm not sure the "mana" section is really viable.

Honestly, D&D spells simply do not work like Nasuverse spells. The prana cost is not directly proportional to the power, and most magi use mana from the surroundings for large spells anyway.

As for Archer, it's pretty obvious that his mana stat has no relationship to his circuit count, and that, in becoming a Servant, he's somehow gained the ability to use a lot more prana than Shirou could.

The rest seems kind-of reasonable, though, although it's difficult to tell for sure.

Andoriol

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Re: Servant Stat Conversions
« Reply #2 on: February 20, 2014, 03:20:42 AM »
Yeah, that's getting torn apart elsewhere as well. I'm struggling to come up with a consistent system to determine a Mana rating. I know that Thaumaturgy is a lot more variable and less structured than D&D spells, but I need to figure out some kind of conversion factor because one of the crossovers I'm definitely involving will be a classic D&D-verse.

Cherry Lover

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Re: Servant Stat Conversions
« Reply #3 on: February 20, 2014, 10:41:11 PM »
Well, there is simply not a direct conversion between the two, because they're different systems. However, individual spells may well be convertable in an ad-hoc manner.

Andoriol

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Re: Servant Stat Conversions
« Reply #4 on: February 20, 2014, 10:45:02 PM »
Definitely not a strict conversion rate, yeah. But general rules would be really helpful, I'm struggling to come up with something or other.

Andoriol

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Re: Servant Stat Conversions
« Reply #5 on: February 27, 2014, 11:49:20 PM »
Okay, here's another go at calculating mana costs. I know, futile, but I think I've got something.

Given:
Shirou's current capacity is ~10 - 20 prana, he has 27 circuits of low quality that can only hold 10 prana each.

Caster's beams of light each cost 3 times Shirou's capacity and require a significant amount of investment from the average mangus in order to cast. These beams can, individually, destroy a Servant.

Rin has a capacity of 500 prana and is a prodigy.

---

Derived:
If the beams' cost was 3 times Shirou's current capacity of 20 and had a cost of 60, then Rin (with a capacity of 500) would be able to fire them off. This does not match up with demonstrated power levels.

If the beams' cost was 3 times Shirou's maximum capacity of 270 and had a cost of ~750, then Rin would be unable to cast them unless she had saved up in something like a gem.

Therefore, the cost of the beams' must be ~750 units of prana.

WIth this, if I know the 'rank' of the attack itself, I can determine a very basic conversion rate between D&D magic and F/SN prana costs. So what do people think the rank of each individual beam of light is? My first guess is B or low A rank.

Cherry Lover

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Re: Servant Stat Conversions
« Reply #6 on: February 28, 2014, 12:00:52 AM »
Again, you're missing the point. Rin couldn't use Caster's beams even if she had an infinite prana supply, because she is simply not capable of casting the spell in question. The prana cost is not directly connected to the power of the spell, and I strongly suspect that the amount of prana Caster uses to cast her spells is actually relatively low.

Andoriol

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Re: Servant Stat Conversions
« Reply #7 on: February 28, 2014, 02:07:16 AM »
Again, you're missing the point. Rin couldn't use Caster's beams even if she had an infinite prana supply, because she is simply not capable of casting the spell in question. The prana cost is not directly connected to the power of the spell, and I strongly suspect that the amount of prana Caster uses to cast her spells is actually relatively low.
Ah, a misunderstanding here. I'm fully aware that Rin can't cast that magic because she doesn't know/can't use the Divine Language. I'm trying to figure out a prana amount for the spell (not exactly the amount Caster uses, I'm with you, I don't think she has all that much prana, though apparently she has enough for two days normally?) to try and derive a general gist of Prana In to Whoopass Out.

If that makes sense. I'm probably not explaining myself well here.

Cherry Lover

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Re: Servant Stat Conversions
« Reply #8 on: February 28, 2014, 02:38:04 AM »
Well, I think I understand. From what I can tell, you're trying to convert every spell into units of Rin-prana, and then measure them accordingly.

I guess that is not necessarily a bad idea (although there is no directly proportional relationship), but I don't think you can really use Caster as an example because her method of casting spells is totally different and likely uses much less prana.

Andoriol

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Re: Servant Stat Conversions
« Reply #9 on: February 28, 2014, 02:44:50 AM »
Sort of, there's obviously no conversion for a lot of it. I mean, come on, D&D has a spell called Limited Wish and freaking WISH. Where they can ressurect the dead, teleport huge distances, alter time, create demiplanes, and other things that are either True Magic or damn close to it. Things that are outright impossible in the Nasuverse, by contrast, the things that a mangus seems able to do with Reinforcement compared to what D&D magic can do in comparable situations is astounding.

But I'm mostly concerned about a conversion rate between blasty-spells, even a basic one. It's obviously not going to be anywhere near perfect, but something is better than nothing in this case, just because of the way I write.

Cherry Lover

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Re: Servant Stat Conversions
« Reply #10 on: February 28, 2014, 01:21:45 PM »
Sort of, there's obviously no conversion for a lot of it. I mean, come on, D&D has a spell called Limited Wish and freaking WISH. Where they can ressurect the dead, teleport huge distances, alter time, create demiplanes, and other things that are either True Magic or damn close to it.

Well, FSN has that to some extent, it's called the Grail. It requires a hell of a lot of prana, though....

Quote
But I'm mostly concerned about a conversion rate between blasty-spells, even a basic one. It's obviously not going to be anywhere near perfect, but something is better than nothing in this case, just because of the way I write.

Sure, I'm just not sure attempting to use Caster as part of the conversion is a good idea, because her magic works totally differently and is a lot stronger. I also think that your focus on the amount of prana used for each D&D spell is a bit off, because that isn't the main point. The main point is more how powerful the spell is.

Also, I suspect the level of the caster would matter. A D&D mage can cast a number of spells per day that increases per level, so by FSN standards it would make sense that the cost of the spells would go down somewhat.

Andoriol

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Re: Servant Stat Conversions
« Reply #11 on: February 28, 2014, 08:08:40 PM »
Sort of, there's obviously no conversion for a lot of it. I mean, come on, D&D has a spell called Limited Wish and freaking WISH. Where they can ressurect the dead, teleport huge distances, alter time, create demiplanes, and other things that are either True Magic or damn close to it.

Well, FSN has that to some extent, it's called the Grail. It requires a hell of a lot of prana, though....
Yeah, but that's explicitly brute-forcing it rather than knowing wtf you're doing. I doubt Aoko or Zeltrech need anywhere near those magnitudes of power to use their Sorceries.

Quote
Quote
But I'm mostly concerned about a conversion rate between blasty-spells, even a basic one. It's obviously not going to be anywhere near perfect, but something is better than nothing in this case, just because of the way I write.

Sure, I'm just not sure attempting to use Caster as part of the conversion is a good idea, because her magic works totally differently and is a lot stronger. I also think that your focus on the amount of prana used for each D&D spell is a bit off, because that isn't the main point. The main point is more how powerful the spell is.
Caster's magic (the Divine Words) seems to roughly parallel a D&D casters magic (and the Arcane Langauge), so in this case it's a fair comparison. But I need a conversion rate because the SIOC has both Thaumaturgy and Arcane magic.

I'm trying to figure out the 'absolute' amount of prana that goes into the spell rather than the amount the caster uses. That's probably impossible, but I'm giving it a shot

Quote
Also, I suspect the level of the caster would matter. A D&D mage can cast a number of spells per day that increases per level, so by FSN standards it would make sense that the cost of the spells would go down somewhat.
Alternatively, they gain a larger internal pool of energy (as per the alternative Spellpower rules).



But really, if I can't assume that cost for Caster then I have nothing to derive at all, there just aren't enough numbers in the Fate-verse for me to figure anything out.

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Re: Servant Stat Conversions
« Reply #12 on: February 28, 2014, 09:03:23 PM »
welcome to the nasuverse, rough estimations are what you get

Cherry Lover

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Re: Servant Stat Conversions
« Reply #13 on: March 02, 2014, 08:10:00 PM »
Sort of, there's obviously no conversion for a lot of it. I mean, come on, D&D has a spell called Limited Wish and freaking WISH. Where they can ressurect the dead, teleport huge distances, alter time, create demiplanes, and other things that are either True Magic or damn close to it.

Well, FSN has that to some extent, it's called the Grail. It requires a hell of a lot of prana, though....
Yeah, but that's explicitly brute-forcing it rather than knowing wtf you're doing. I doubt Aoko or Zeltrech need anywhere near those magnitudes of power to use their Sorceries.

Yeah, probably, but I don't think it's a much worse comparison than using an extremely-powerful sorceress as the baseline....

Quote
Caster's magic (the Divine Words) seems to roughly parallel a D&D casters magic (and the Arcane Langauge), so in this case it's a fair comparison. But I need a conversion rate because the SIOC has both Thaumaturgy and Arcane magic.

Sure, but unforunately her magic is not "roughly parallel" to modern Nasuverse magic, so that doesn't really help one bit. For example, Caster's magic does not use magic circuits, and they have no concept of a "magic crest" or similar.

Quote
I'm trying to figure out the 'absolute' amount of prana that goes into the spell rather than the amount the caster uses. That's probably impossible, but I'm giving it a shot

Yes, the problem is that Caster's magic has about as much in common with Rin's as D&D magic does, so it's not really a helpful comparison.

Quote
Alternatively, they gain a larger internal pool of energy (as per the alternative Spellpower rules).

The problem is that that doesn't fit with how Nasuverse magic actually works. For one thing, you can't "learn" to have a larger pool of energy, whereas you can learn to use better spells and use the spells you do have at less cost. Trying to convert it in that way leads to inconsistencies if you attempt to convert Nasuverse-learnt magic into the D&D world and then back again.

Quote
But really, if I can't assume that cost for Caster then I have nothing to derive at all, there just aren't enough numbers in the Fate-verse for me to figure anything out.

Well, yeah, unfortunately Nasu doesn't really give any numbers.

However, what you can say is that Rin's jewels are approximately as powerful as one of Caster's spells, and try to work from there. But, even then, you don't have any reasonable indication of what level Rin would be in a D&D world, and I am not remotely convinced that that particular spell is a good conversion point, because I think it's considerably "easier" in D&D than in the Nasuverse and, further, the version of it that Caster is doing is an extremely high-level version and other magi could probably do a worse but much-cheaper version of the same thing.

If you try to do it that way, the conclusion you will come to is that D&D magic is really overpowered relative to Nasuverse magic and that Nasuverse magi in the D&D verse would be unable to use almost any of their spells more than once a day (if that).

Honestly, if you need to make a direct conversion, you need to look at more than one spell and you need to use a normal magus. Rin is quite powerful (although relatively untrained), she shouldn't be coming out as a level 1 sorcerer, especially if you're using the prana pool as a baseline. If she is then the comparison is miles out.

However, I think you're probably screwed here, because the D&D system is far more rigid and less complex. For example, Sakura has almost no training, but yet she has a prana pool equal to Rin's (without the worms, anyway). Therefore she has the potential to be a lot more powerful than an average magus if she is able to train properly. Conversely, someone like Shirou 10 years after FSN might be well-trained, but his prana pool is much lower. I don't see how you could model that in D&D terms.
« Last Edit: March 02, 2014, 08:15:09 PM by Cherry Lover »

Andoriol

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Re: Servant Stat Conversions
« Reply #14 on: March 03, 2014, 05:50:24 AM »
welcome to the nasuverse, rough estimations are what you get
CUUUURRRSSEEEE YOOOOUUUUU NAAAASSSUUUUUUUU!!!

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Alternatively, they gain a larger internal pool of energy (as per the alternative Spellpower rules).
The problem is that that doesn't fit with how Nasuverse magic actually works. For one thing, you can't "learn" to have a larger pool of energy, whereas you can learn to use better spells and use the spells you do have at less cost. Trying to convert it in that way leads to inconsistencies if you attempt to convert Nasuverse-learnt magic into the D&D world and then back again.
Actually, I always found it weird that in order to gain levels in D&D as a spellcaster, you had to go into combat.

The tentative Idea I have at the moment is that in a higher mana/Grain environment, spellcasters can essentially 'exercise their magic muscles', stretching their internal capacity completely unrelated to magic circuits. Never to any serious amounts in a world like the classic D&D setting, but a decent amount. The Arcane Language / Divine Words multiplies this by speaking directly to the world and making shit happen. Greater skill with the language as well as energy expenditure on the users behalf increase the power and number of spells they can cast.

Again, tentative concept here.

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But really, if I can't assume that cost for Caster then I have nothing to derive at all, there just aren't enough numbers in the Fate-verse for me to figure anything out.

Well, yeah, unfortunately Nasu doesn't really give any numbers.

However, what you can say is that Rin's jewels are approximately as powerful as one of Caster's spells, and try to work from there. But, even then, you don't have any reasonable indication of what level Rin would be in a D&D world, and I am not remotely convinced that that particular spell is a good conversion point, because I think it's considerably "easier" in D&D than in the Nasuverse and, further, the version of it that Caster is doing is an extremely high-level version and other magi could probably do a worse but much-cheaper version of the same thing.

If you try to do it that way, the conclusion you will come to is that D&D magic is really overpowered relative to Nasuverse magic and that Nasuverse magi in the D&D verse would be unable to use almost any of their spells more than once a day (if that).

Honestly, if you need to make a direct conversion, you need to look at more than one spell and you need to use a normal magus. Rin is quite powerful (although relatively untrained), she shouldn't be coming out as a level 1 sorcerer, especially if you're using the prana pool as a baseline. If she is then the comparison is miles out.

However, I think you're probably screwed here, because the D&D system is far more rigid and less complex. For example, Sakura has almost no training, but yet she has a prana pool equal to Rin's (without the worms, anyway). Therefore she has the potential to be a lot more powerful than an average magus if she is able to train properly. Conversely, someone like Shirou 10 years after FSN might be well-trained, but his prana pool is much lower. I don't see how you could model that in D&D terms.
D&D is a system to emulate combat, nothing more or less. It's a level-based system in contrast to a more (effectively) point-buy system like the Nasuverse.

To get something closer to emulating Nasuverse magic, it's better to use Psionics actually, and assume that characters' Power Points are determined by their 'Magic Circuits', with feats and things representing greater efficiency with magic. In that situation, it'd actually be a relatively easy and faithful conversion. The trick is converting the numbers so I have a point of comparison, which is really fucking hard. If I could get numbers for any spell that I can reasonably go "Okay, this seems X difficult for Y, who is Z competent" and then ballpark it from there.