Potent Dragonmark and Spell Preparation. (Eberron: Forge of the Artificer)

Quote from Squirrelloid >>

Quote from Lia_Black >>

I don't see any wording that limits the feats to adding the spells to a single Spellcasting feature or class so I would argue that if you multi class, it adds it to all of the specified features and that they are like wise always prepared under those features.

Spell slots are not class specific, but Pact Magic slots are, so I would count the Potent Dragonmark free slot as a regular spell slot but not as a Pact Magic slot.

 Pact Magic slots are not class specific, either.  If you're a Warlock/Sorceror, you can cast Warlock spells with your regular spell slots, and Sorceror spells with your Warlock spell slots.  (And indeed, you can even turn Warlock spell slots into Sorceror Points).

The only difference between Pact Magic and other slots is you don't add your Warlock levels to your other spellcasting levels and determine a joint spell slot set from that total, the number of Warlock slots are determined solely by your Warlock level.

I think what Lia_Black meant (correct me if I am wrong) is that when you multiclass, the classes with the Spellcasting feature combine to create your spell slots available per the Multiclass table. Pact Magic remains separate. Yes, you can use the any slots to cast any spell, but Pact Magic slots do remain independent.

Quote from TarodNet >>

Dragonmark Stuff Combined:  You always have the spells on your Spells of the Mark list prepared --- (NOTE: unlike other feats, here we don't have "You can also cast these spells using spell slots you have of the appropriate level") 

 

I don't think that text is actually necessary in 2024. If a spell is prepared, you can cast it with slots you have of the appropriate level. I think existing Feats mention it as hold overs from 2014 or to reinforce the change from 2014. However, the requirement to cast a level 1+ spell is that you need to have it prepared and have an appropriate spell slot available. There's not really any other requirement that I can think of.

Quote from SmiteMakesRight_3_5 >>

I think what Lia_Black meant (correct me if I am wrong) is that when you multiclass, the classes with the Spellcasting feature combine to create your spell slots available per the Multiclass table. Pact Magic remains separate. Yes, you can use the any slots to cast any spell, but Pact Magic slots do remain independent.

 This is correct. 

Edit: Also there are features that specifically call out the use of Pact Slots (Eldritch Smite), though Potent Dragonmark states that it can only be used for the Dragonmark Spells so it doesn't really impact the discussion.

Quote from SmiteMakesRight_3_5 >>

Quote from TarodNet >>

Dragonmark Stuff Combined:  You always have the spells on your Spells of the Mark list prepared --- (NOTE: unlike other feats, here we don't have "You can also cast these spells using spell slots you have of the appropriate level")  

I don't think that text is actually necessary in 2024. If a spell is prepared, you can cast it with slots you have of the appropriate level. I think existing Feats mention it as hold overs from 2014 or to reinforce the change from 2014. However, the requirement to cast a level 1+ spell is that you need to have it prepared and have an appropriate spell slot available. There's not really any other requirement that I can think of.

 I'm not totally sure about this, honestly. If that wording appears in traits and feats, it must be there for a reason.

Or maybe not, and it's like you're saying.

Quote from TarodNet >>

Quote from SmiteMakesRight_3_5 >>

Quote from TarodNet >>

Dragonmark Stuff Combined:  You always have the spells on your Spells of the Mark list prepared --- (NOTE: unlike other feats, here we don't have "You can also cast these spells using spell slots you have of the appropriate level")  

I don't think that text is actually necessary in 2024. If a spell is prepared, you can cast it with slots you have of the appropriate level. I think existing Feats mention it as hold overs from 2014 or to reinforce the change from 2014. However, the requirement to cast a level 1+ spell is that you need to have it prepared and have an appropriate spell slot available. There's not really any other requirement that I can think of.

 I'm not totally sure about this, honestly. If that wording appears in traits and feats, it must be there for a reason.

Or maybe not, and it's like you're saying.

 They are added to the class's spellcasting feature so the ability to cast it with your other slots comes from the class's existing feature.

Note: No other feat adds the given spells to your class thus the reason the verbage for slots is required. 

Just writing out your ruling to see if I'm understanding all of you correctly after reading the last posts:

- When you take Potent Dragonmark, all Spells of the Mark (e.g. Mark of Storm Spells) are prepared for all your classes.

- You can cast any of those spells using your own slots, and you choose which Spellcasting Ability to use (if you have more than one) whenever you cast them.

- Additionally, you can cast any of those spells using the free spell slot provided by Potent Dragonmark (half your level (round up), to a maximum of level 5), and you choose which Spellcasting Ability to use (if you have more than one) whenever you cast them.

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

Quote from IMmoRtAlREapER >>

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

 IMO, it's ok.

Quote from IMmoRtAlREapER >>

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

I agree with TarodNet — I don't see anything in the rules for either feature saying you can't do that.

There's a potential abuse case in turning it into sorcery points and then immediately turning those back into an unrestricted spell slot, but the lopsided exchange rate between spell slots and sorcery points means that's a bad bet most of the time, so I don't think it's really an issue in practice.

Quote from IMmoRtAlREapER >>

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

I am going to say that it's iffy. Potent Dragonmark says "You can use this spell slot to cast only a spell you have prepared because of your Dragonmark feat or the Dragonmark Preparation benefit of this feat."

The placement of "only" is awkward, but I think that it means that only use of the spell slot is to cast Dragonmark spells. If had said "You can only use this spell slot", it would definitely not be allowed. However, because it says to "to cast only a spell", this can be taken to mean that when used to cast a spell, you can only cast these spells, but it can also be read as you can only use it to cast a spell and only these spells.

I would personally lean towards it's not allowed.

Quote from SmiteMakesRight_3_5 >>

Quote from IMmoRtAlREapER >>

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

I am going to say that it's iffy. Potent Dragonmark says "You can use this spell slot to cast only a spell you have prepared because of your Dragonmark feat or the Dragonmark Preparation benefit of this feat."

The placement of "only" is awkward, but I think that it means that only use of the spell slot is to cast Dragonmark spells. If had said "You can only use this spell slot", it would definitely not be allowed. However, because it says to "to cast only a spell", this can be taken to mean that when used to cast a spell, you can only cast these spells, but it can also be read as you can only use it to cast a spell and only these spells.

I would personally lean towards it's not allowed.

 But why does that take precedence over the Level 2: Font of Magic feature? I mean, they're equally potent (pun intended). To me, one is not more specific than the other.

Converting Spell Slots to Sorcery Points. You can expend a spell slot to gain a number of Sorcery Points equal to the slot’s level (no action required).

Quote from TarodNet >>

Quote from SmiteMakesRight_3_5 >>

Quote from IMmoRtAlREapER >>

Can you turn the potent mark spell slot into Sorcery points using Font of Magic?

I am going to say that it's iffy. Potent Dragonmark says "You can use this spell slot to cast only a spell you have prepared because of your Dragonmark feat or the Dragonmark Preparation benefit of this feat."

The placement of "only" is awkward, but I think that it means that only use of the spell slot is to cast Dragonmark spells. If had said "You can only use this spell slot", it would definitely not be allowed. However, because it says to "to cast only a spell", this can be taken to mean that when used to cast a spell, you can only cast these spells, but it can also be read as you can only use it to cast a spell and only these spells.

I would personally lean towards it's not allowed.

 But why does that take precedence over the Level 2: Font of Magic feature? I mean, they're equally potent (pun intended). To me, one is not more specific than the other.

Converting Spell Slots to Sorcery Points. You can expend a spell slot to gain a number of Sorcery Points equal to the slot’s level (no action required).

I can see that argument. I guess you wind up with a spell slot that:

• You can expend to gain a number of Sorcery Points equal to the slot's level
• You can use to cast only dragonmark spells

Font of Magic doesn't remove the restriction on how you can use the slot, so it still comes down to whether the restriction is the spells you can cast when you cast a spell or what you can do with the spell slot at all.

The question applies to any effect that requires expending a spell slot, like Eldritch Smite, Wild Resurgence, or Hat of Many Spells (which, unlike Font of Magic, would mostly delete the restriction on the spell slot).

I would still lean towards it's not allowed.

I fully understand your POV, and I would agree that it is a valid ruling as well.

It's just that I think Font of Magic can override Potent Dragonmark. I also think the opposite could be true. So it's a tie, and for this reason, I think it's equally valid to rule that the interaction is allowed.

Spells of the Mark says

If you have the Spellcasting or Pact Magic class feature, the spells on the Mark of Storm Spells table are added to that feature’s spell list.

This means that the spells are added to your spell list.

And as you quoted

A class’s spell list specifies the spells that belong to the class. For example, a Sorcerer spell is a spell on the Sorcerer spell list, and if a Sorcerer knows spells that aren’t on that list, those spells aren’t Sorcerer spells unless a feature says otherwise.

And the Spells of the Mark feature did say otherwise, so they are Sorcerer spells. And this means that you can use an Arcane Focus with it.

Concerning Wild Magic Surge, you quoted

From the multiclassing rules: “Each spell you prepare is associated with one of your classes.” This rule means only the spells prepared as part of your Sorcerer class features trigger Wild Magic Surge.

and

Your spellcasting can unleash surges of untamed magic. Once per turn, you can roll 1d20 immediately after you cast a Sorcerer spell with a spell slot. If you roll a 20, roll on the Wild Magic Surge table to create a magical effect.

We know that it is a Sorcerer spell and as long as you cast it with a spell slot, the latter part is fulfilled. As for the former part, the Spells of the Mark feature says that the spells are added to the Sorcerer class feature's spell list, so that part is also fulfilled.

As far as the "prepared" aspect goes, Potent Dragonmark's Dragonmark Preparation feature says

You always have the spells on your Spells of the Mark list (if any) prepared.

which is similar to the Sorcerer subclass features which say in the case of Draconic Sorcery

When you reach a Sorcerer level specified in the Draconic Spells table, you thereafter always have the listed spells prepared.

which explicitly tells you that the spells are considered "prepared". Whether they are "prepared" because you chose to prepare them or whether they are prepared through any of those features is irrelevant.

And, if you take it all together, they still trigger Wild Surge, regardless of how they are prepared because the spells were added to your Spellcasting feature and are prepared as such as part of your Sorcerer class feature because Spells of the Mark added them to your Spellcasting feature and Dragonmark Preparation made them prepared as part of that Spellcasting feature. If you get very picky with the exact wording of the Errata and argue that the spell was prepared as part of a feat and not as part of a Sorcerer feature, you have to also consider the question it answered, hence the context of the answer which was

A Wizard multiclasses into a Sorcerer with the Wild Magic Sorcery subclass. Do spells cast from their spellbook trigger Wild Magic Surge if they are on the Sorcerer spell list, or do they have to gain them from Sorcerer to trigger?

and this situation is inherently different from a multiclass character who prepared spells as part of another class.

Also, you could argue that the feat is a Sorcerer Class Feature because it is taken as part of the Ability Score Improvement feature which is explicitly listed as a Sorcerer class feature and says

You gain the Ability Score Improvement feat (see chapter 5) or another feat of your choice for which you qualify. You gain this feature again at Sorcerer levels 8, 12, and 16.

And not only is "Ability Score Improvement" listed in the text of the Sorcerer class features, if you look at the table of the Sorcerer Class Features and the column titled "class features", it also lists "Ability Score Improvement" in that very column.

In the previous page and in a related thread (*), some folks (me included) were commenting that the multiclassing answer from the SAC is problematic because it contradicts the general SAC answer about what counts as class spells. So, in my opinion, if you use only the general one, it's easier to rule interactions like the one proposed here.

(*) Feat granted spells and how they apply. Also here Cantrip questions when Multiclassing [2024] (comment #31)

Regarding the feat being a class feature because it was taken as part of the Ability Score Improvement feature, it doesn't seem to be:

Quote from TarodNet >>

Quote from Kasanovin >>

Secondarily and closely related to this threads topic, but again referencing some of the things I've seen on other threads. Can anyone provide some clarity on why it seems to be the general consensus of this forum that the langauge in many spellcasting classes (though not Eldritch Knight in particular) of "If another [class] feature gives spells that you always have prepared, those spells don’t count against the number of spells on the list you prepare with this feature, but those spells otherwise count as [class] spells for you." wouldn't apply to 2024 magic initiate if it were taken with this class feature "Level 4: Ability Score Improvement You gain the Ability Score Improvement feat or another feat of your choice for which you qualify. You gain this feature again at Warlock levels 8, 12, and 16."

 Because a feat, even when gained through a feature, is not a feature, at least based on the following information from the PHB: 

Chapter 5: Feats
This chapter offers a collection of feats, which are special features not tied to a character class. [...] Your background gives you a feat, and at certain levels, your class gives you the Ability Score Improvement feat or the choice of another feat for which you qualify.

And this information from the Converting to System Reference Document 5.2.1:

Quote from TarodNet >>

Reading the Converting to System Reference Document 5.2.1, maybe this helps regarding the discussion about whether feats (e.g. Ability Score Improvement) are considered class features or a separate thing:

Feats

Feats “Feats” includes the following new and revised elements, which are presented in the order in which they appear in that section.

Feat Descriptions [New Rule]

Feats are now divided into categories, including Origin, General, Fighting Style, and Epic Boon. All feats in this section are new except for the following revised rules.

Ability Score Improvement [Revised Rule]

This rule is now a feat rather than a class feature.

Grappler [Revised Rule]

This feat is revised and is now a General feat.

Fighting Style Feats [Revised Rule]

These rules are now feats rather than class features.

Quote from Ancoulainn >>

Concerning Wild Magic Surge, you quoted

From the multiclassing rules: “Each spell you prepare is associated with one of your classes.” This rule means only the spells prepared as part of your Sorcerer class features trigger Wild Magic Surge.

and

Your spellcasting can unleash surges of untamed magic. Once per turn, you can roll 1d20 immediately after you cast a Sorcerer spell with a spell slot. If you roll a 20, roll on the Wild Magic Surge table to create a magical effect.

We know that it is a Sorcerer spell and as long as you cast it with a spell slot, the latter part is fulfilled. As for the former part, the Spells of the Mark feature says that the spells are added to the Sorcerer class feature's spell list, so that part is also fulfilled.

As far as the "prepared" aspect goes, Potent Dragonmark's Dragonmark Preparation feature says

You always have the spells on your Spells of the Mark list (if any) prepared.

which is similar to the Sorcerer subclass features which say in the case of Draconic Sorcery

When you reach a Sorcerer level specified in the Draconic Spells table, you thereafter always have the listed spells prepared.

which explicitly tells you that the spells are considered "prepared". Whether they are "prepared" because you chose to prepare them or whether they are prepared through any of those features is irrelevant.

According to Sage Advice, how you prepare the spell is very much relevant.

A Wizard multiclasses into a Sorcerer with the Wild Magic Sorcery subclass. Do spells cast from their spellbook trigger Wild Magic Surge if they are on the Sorcerer spell list, or do they have to gain them from Sorcerer to trigger?

From the multiclassing rules: “Each spell you prepare is associated with one of your classes.” This rule means only the spells prepared as part of your Sorcerer class features trigger Wild Magic Surge.

According to the Sage Advice, having a spell prepared via Potent Dragonmark is not sufficient for it to count as a Sorcerer spell. You must select it as a spell you have prepared as per your Sorcerer class or it doesn't count. Being prepared via Potent Dragonmark only means that it is available for casting and nothing else. It is not a Sorcerer spell, a Wizard spell, a Bard spell, or any other spell until you prepare it as that class. If you want a spell to be cast as a Sorcerer spell and a Wizard spell, you need to prepare it twice, once as a Sorcerer and once as a Wizard. 

Quote from Ancoulainn>>

And, if you take it all together, they still trigger Wild Surge, regardless of how they are prepared because the spells were added to your Spellcasting feature and are prepared as such as part of your Sorcerer class feature because Spells of the Mark added them to your Spellcasting feature and Dragonmark Preparation made them prepared as part of that Spellcasting feature.

This is incorrect. Potent Dragonmark makes them prepared but not prepared as part of that Spellcasting feature.

Quote from Ancoulainn >>

Also, you could argue that the feat is a Sorcerer Class Feature because it is taken as part of the Ability Score Improvement feature which is explicitly listed as a Sorcerer class feature and says

You gain the Ability Score Improvement feat (see chapter 5) or another feat of your choice for which you qualify. You gain this feature again at Sorcerer levels 8, 12, and 16.

And not only is "Ability Score Improvement" listed in the text of the Sorcerer class features, if you look at the table of the Sorcerer Class Features and the column titled "class features", it also lists "Ability Score Improvement" in that very column.

This isn't clear, however, please look at Rhythm of Play.

Exceptions Supersede General Rules

General rules govern each part of the game. For example, the combat rules tell you that melee attacks use Strength and ranged attacks use Dexterity. That’s a general rule, and a general rule is in effect as long as something in the game doesn’t explicitly say otherwise.

The game also includes elements—class features, feats, weapon properties, spells, magic items, monster abilities, and the like—that sometimes contradict a general rule. When an exception and a general rule disagree, the exception wins. For example, if a feature says you can make melee attacks using your Charisma, you can do so, even though that statement disagrees with the general rule.

Notice that Class Features and Feats are separate game elements.

As TarodNet mentioned, the particular Sage Advice ruling is problematic. It explicitly defines how spell is prepared affects whether it is a class spell. However, it also contradicts other rules and sage advice about determining what a class spell is. By RAW, spells only prepared by Potent Dragonmark will never trigger Wild Magic or other class features dependent on casting a class spell. However, discuss it with the DM because of the contentious nature of that ruling.

Quote from SmiteMakesRight_3_5>>

Quote from Ancoulainn>>

Concerning Wild Magic Surge, you quoted

From the multiclassing rules: “Each spell you prepare is associated with one of your classes.” This rule means only the spells prepared as part of your Sorcerer class features trigger Wild Magic Surge.

and

Your spellcasting can unleash surges of untamed magic. Once per turn, you can roll 1d20 immediately after you cast a Sorcerer spell with a spell slot. If you roll a 20, roll on the Wild Magic Surge table to create a magical effect.

We know that it is a Sorcerer spell and as long as you cast it with a spell slot, the latter part is fulfilled. As for the former part, the Spells of the Mark feature says that the spells are added to the Sorcerer class feature's spell list, so that part is also fulfilled.

As far as the "prepared" aspect goes, Potent Dragonmark's Dragonmark Preparation feature says

You always have the spells on your Spells of the Mark list (if any) prepared.

which is similar to the Sorcerer subclass features which say in the case of Draconic Sorcery

When you reach a Sorcerer level specified in the Draconic Spells table, you thereafter always have the listed spells prepared.

which explicitly tells you that the spells are considered "prepared". Whether they are "prepared" because you chose to prepare them or whether they are prepared through any of those features is irrelevant.

According to Sage Advice, how you prepare the spell is very much relevant.

A Wizard multiclasses into a Sorcerer with the Wild Magic Sorcery subclass. Do spells cast from their spellbook trigger Wild Magic Surge if they are on the Sorcerer spell list, or do they have to gain them from Sorcerer to trigger?

From the multiclassing rules: “Each spell you prepare is associated with one of your classes.” This rule means only the spells prepared as part of your Sorcerer class features trigger Wild Magic Surge.

According to the Sage Advice, having a spell prepared via Potent Dragonmark is not sufficient for it to count as a Sorcerer spell. You must select it as a spell you have prepared as per your Sorcerer class or it doesn't count. Being prepared via Potent Dragonmark only means that it is available for casting and nothing else. It is not a Sorcerer spell, a Wizard spell, a Bard spell, or any other spell until you prepare it as that class. If you want a spell to be cast as a Sorcerer spell and a Wizard spell, you need to prepare it twice, once as a Sorcerer and once as a Wizard. 

That is incorrect as stated. If you have Potent Dragonmark, you also have to have a Dragonmark feat and Spells of the Mark says that the spell is added to your Spellcasting feature and the associated spell list which, in this case, makes it a Sorcerer spell. As per the Sage Advice & Errate, a spell is a Sorcerer spell if it is on the Sorcerer's spell list which is achieved via the Dragonmark feat. Whether it counts as prepared as part of your Sorcerer class features is a separate issue and that requires to define what it means to have a spell prepared as part of a Sorcerer class feature. 

Quote from Ancoulainn>>

And, if you take it all together, they still trigger Wild Surge, regardless of how they are prepared because the spells were added to your Spellcasting feature and are prepared as such as part of your Sorcerer class feature because Spells of the Mark added them to your Spellcasting feature and Dragonmark Preparation made them prepared as part of that Spellcasting feature.

This is incorrect. Potent Dragonmark makes them prepared but not prepared as part of that Spellcasting feature.

The problem with that statement is that we don't have a clear definition as to what that means. We know, when you gain a level in Sorcerer and add a spell as outlined in the Sorcerer's Spellcasting feature, that spell is prepared as part of a Sorcerer class feature. We also know, when you gain a level in a different spellcasting class and add a spell as outlined in their respective feature, that spell is not prepared as part of a Sorcerer class feature. But for everything in between, we do not know. Specifically, as you pointed out, it is unclear whether feats taken as part of the Ability Score Improvement, in particular feats that add to the class features, are to be considered as sufficient in this manner. On the one hand, the Ability Score Improvement is listed under class features as I mentioned earlier. On the other hand, there are a number of statements in the rules that at least seem to differentiate between feats and class features. However, when dealing with such contradictions, it is always best to go with the most specific statements rather than statements that actually focus on something else and just make a mention in passing such as what TarodNet mentions or what you mentioned in Rhythm of Play. And the most specific one is the one that lists Ability Score Improvements under Class Features in the respective class descriptions. And based on that, Ability Score Improvements are a class feature.

But I understand that opinions on this differ. It is not that different from the question whether Epic Boon feats are available when multiclassing because, on the one hand, they are listed under class features for level 19 of the specific classes, and, on the other hand, their prerequisite says "level 19+", not "level 19+ class" like it does for Warlock Invocations. But in this context, we also have to consider that the designers of WotC aren't lawyers who trained for years to spell out rules in the most precise language possible and we know even they fail often enough when drafting rules, regulations, and laws.

We know the spell is on the spell list that is associated with the Spellcasting feature because Spells of the Mark says so. We also know that the spell is prepared because Potent Dragonmark says so. So, the differentiation you make here boils down to that the spell in question is part of the Spellcasting feature, because Spells of the Mark says so, but not prepared as part of that Spellcasting feature because it's prepared through the Potent Dragonmark feat. And with the lack of clarity whether feats taken as part of the Ability Score Improvement as class features, we add an additional differentiation on top: That feats are gained through a class feature, as Kasanovin put it, but are not class features themselves. To me, that's way too thin.

Quote from Ancoulainn>>

Also, you could argue that the feat is a Sorcerer Class Feature because it is taken as part of the Ability Score Improvement feature which is explicitly listed as a Sorcerer class feature and says

You gain the Ability Score Improvement feat (see chapter 5) or another feat of your choice for which you qualify. You gain this feature again at Sorcerer levels 8, 12, and 16.

And not only is "Ability Score Improvement" listed in the text of the Sorcerer class features, if you look at the table of the Sorcerer Class Features and the column titled "class features", it also lists "Ability Score Improvement" in that very column.

This isn't clear, however, please look at Rhythm of Play.

Exceptions Supersede General Rules

General rules govern each part of the game. For example, the combat rules tell you that melee attacks use Strength and ranged attacks use Dexterity. That’s a general rule, and a general rule is in effect as long as something in the game doesn’t explicitly say otherwise.

The game also includes elements—class features, feats, weapon properties, spells, magic items, monster abilities, and the like—that sometimes contradict a general rule. When an exception and a general rule disagree, the exception wins. For example, if a feature says you can make melee attacks using your Charisma, you can do so, even though that statement disagrees with the general rule.

Notice that Class Features and Feats are separate game elements.

Yes, they are mentioned separately in a section that discusses that exceptions to the rules override general rules. There are also the sections that TarodNet quoted from the SRD. And then they are listed as separate topics in the Sage Advice & Errata. But in the class descriptions, Ability Score Improvements are listed under class features. I agree that this is a contradiction, but as I mentioned earlier, in such cases, it's always better to go with the most specific information and that is in the class descriptions. But, as you said, it is unclear and I wouldn't scold anyone who would go against that.

As TarodNet mentioned, the particular Sage Advice ruling is problematic. It explicitly defines how spell is prepared affects whether it is a class spell. However, it also contradicts other rules and sage advice about determining what a class spell is. By RAW, spells only prepared by Potent Dragonmark will never trigger Wild Magic or other class features dependent on casting a class spell. However, discuss it with the DM because of the contentious nature of that ruling.

 It actually does not affect whether it is a class spell. It affects whether casting the spell triggers Wild Surge. If you argue that spells prepared via Potent Dragonmark are not prepared as part of the Sorcerer class features and therefore do not trigger Wild Surge, that does not mean that the respective spell is not a Sorcerer spell. In fact, even if you hold that view, Spells of the Mark still makes it a Sorcerer spell. Casting that Sorcerer spell just wouldn't trigger Wild Surge. Thus, if the trigger for a class feature would be casting a class spell, it would still trigger. It just wouldn't trigger if the requirement is that the spell is prepared as part of a class feature and if you don't consider the Potent Dragonmark feat as a class feature. In short, the question whether a spell is a class spell and the question whether a spell was prepared as part of a class feature are separate issues.

And since, as you said, it is unclear whether feats like Potent Dragonmark are class features, it also cannot be said that RAW spells only prepared by Potent Dragonmark would never trigger Wild Magic because that is dependent upon whether they are class features or not. Personally, I think the much better argument is for that they are, but I'm far from the point of saying that one is definitely right and the other is definitely wrong and neither is anybody else, no matter what they think.

All I can say is that as a DM, I do not make the aforementioned distinctions, because I simply find them too thin to justify them and fellow DMs that I play with as a player don't do that either. As the 2014 DMG said

The D&D rules help you and the other players have a good time, but the rules aren’t in charge. You’re the DM, and you are in charge of the game.

And as Jeremy Crawford reiterated in his article "Philosophy Behind Rules and Rulings"

The direction we chose for the current edition was to lay a foundation of rules that a DM could build on, and we embraced the DM’s role as the bridge between the things the rules address and the things they don’t.

Thus, when it comes to narrow cases like this and even beyond that, it is what the DM says it is. And when you don't like what the DM says, find a different table that's more to your liking. It's not personal. And both as a player and a DM, I can only recommend to always discuss everything with your DM, no matter what it is. If you want to take a specific combination of feats, discuss it with the DM. If you are considering specific spell interactions, discuss it with the DM. Whatever you're planning on doing, discuss it with the DM. If it's worth the time to plan, it is worth the time to share it with the DM. Not only does that ensure that you're on the same page rule-wise, but it also lets the DM know what you're planning and allows them to set the scene for you to shine, not only narratively but also mechanically. Cheers!

Quote from Ancoulainn >>

According to the Sage Advice, having a spell prepared via Potent Dragonmark is not sufficient for it to count as a Sorcerer spell. You must select it as a spell you have prepared as per your Sorcerer class or it doesn't count. Being prepared via Potent Dragonmark only means that it is available for casting and nothing else. It is not a Sorcerer spell, a Wizard spell, a Bard spell, or any other spell until you prepare it as that class. If you want a spell to be cast as a Sorcerer spell and a Wizard spell, you need to prepare it twice, once as a Sorcerer and once as a Wizard. 

SAC doesn't say that at all. It says that you have to have the spell "prepared as part of your Sorcerer class features" to trigger Wild Surge and it does that within the context of a specific question involving another class' Spellcasting feature. As such, it only tells you that a spell prepared as part of another class' Spellcasting feature will not suffice to trigger Wild Surge. Nothing more, nothing less. Anything beyond that is conjecture.

The only crucial part here is the mentioning of "Sorcerer class features". First of all, this refers to any Sorcerer class feature, not just the Sorcerer Spellcasting feature which is not mentioned here at all. But even if it were, the respective spells are added to the Sorcerer's Spellcasting feature because Spells of the Mark says "If you have the Spellcasting or Pact Magic class feature, the spells on the Mark of Making Spells table are added to that feature’s spell list." And since having a Dragonmark feat with Spells of the Mark is a prerequisite for Potent Dragonmark, these spells are part of the class' Spellcasting feature.

It is irrelevant that that are on the class's spell list if they are not prepared according to the class's spellcasting feature, which for a Sorcerer says:

Spellcasting:

Prepared Spells of Level 1+. You prepare the list of level 1+ spells that are available for you to cast with this feature. To start, choose two level 1 Sorcerer spells. Burning Hands and Detect Magic are recommended.

The number of spells on your list increases as you gain Sorcerer levels, as shown in the Prepared Spells column of the Sorcerer Features table. Whenever that number increases, choose additional Sorcerer spells until the number of spells on your list matches the number in the Sorcerer Features table. The chosen spells must be of a level for which you have spell slots. For example, if you’re a level 3 Sorcerer, your list of prepared spells can include six Sorcerer spells of level 1 or 2 in any combination.

If another Sorcerer feature gives you spells that you always have prepared, those spells don’t count against the number of spells you can prepare with this feature, but those spells otherwise count as Sorcerer spells for you.

Changing Your Prepared Spells. Whenever you gain a Sorcerer level, you can replace one spell on your list with another Sorcerer spell for which you have spell slots.

If you do not select spells according to the above feature to be a prepared spell, or have a class feature - not a feat, that causes the spell to always be prepared, it is not a Sorcerer spell. Potent Dragonmark does not prepare the spell as a Sorcerer spell. There is no particular evidence that I can think of to support that it is intended to.

Quote from Ancoulainn >>

Also, Spells of the Mark makes them Sorcerer spell because Spells of the Mark adds them to the Spellcasting class feature and that feature's spell list and SAC says

Which of a character’s spells count as class spells? For example, if I’m playing a Sorcerer, which of my character’s spells are Sorcerer spells?

A class’s spell list specifies the spells that belong to the class. For example, a Sorcerer spell is a spell on the Sorcerer spell list, and if a Sorcerer knows spells that aren’t on that list, those spells aren’t Sorcerer spells unless a feature says otherwise.

This Sage Advice is contradicted by the Sage Advice on preparing spells. 

Quote from Ancoulainn>>

The only question that remains is whether they are "prepared as part of your Sorcerer class features" if they are prepared via Potent Dragonmark and whether the feat is considered a class feature. 

Feats are not class features. Nothing defines them definitively as such, but the rules does instead call them out as separate concepts.

Quote from Ancoulainn>>

As TarodNet mentioned, the particular Sage Advice ruling is problematic. It explicitly defines how spell is prepared affects whether it is a class spell. However, it also contradicts other rules and sage advice about determining what a class spell is. By RAW, spells only prepared by Potent Dragonmark will never trigger Wild Magic or other class features dependent on casting a class spell. However, discuss it with the DM because of the contentious nature of that ruling.

It doesn't say any of that. It says that Wild Surge is only triggered if it is a spell that is prepared as part of the Sorcerer class features and a statement about Wild Surge is not a statement about what constitutes a prepared spell or a class spell.

Exactly. It says exactly that. The gap you are missing is that Potent Dragonmark is not a class feature and therefore spells only prepared via Potent Dragonmark are never class spells per that Sage Advice. 

Quote from Ancoulainn >>

And as you stated

This isn't clear

so, RAW, at best, it isn't clear and definitely not 

By RAW, spells only prepared by Potent Dragonmark will never trigger Wild Magic or other class features dependent on casting a class spell.

which is conjecture at best and not actually what it says without overly reading into it and extrapolating the information beyond the wording and context of the statements at hand.

And for the campaigns I DM, I follow the above-mentioned reasons and in the campaigns I'm a player, the DM agrees with me for the same reasons. 

You have chopped my quote, changing the context. The rules separate Class Features and Feats, but it is not clear; it is tucked away in another rule rather than in a definition of a feat or a class feature.

You have made assumptions about the rules that aren't actually supported by them. I consider it important to understand the RAW and RAI before making house rules, but honestly, I feel that this SAC/SAnE ruling to be problematic. It's of course fine if you want to base your house rules on your misunderstanding, but you should take time to evaluate the impact of wide selection of prepared spells freely interacting with class features of a class balanced around a narrow selection.

Additionally, when advocating a position that has no (or little) RAW support, you should be clear about it as the implementation may vary by table.

Since I already addressed all of your points previously, all I can say is that, in the end, you think that you understand RAW and RAI and that I misunderstand and I think that I understand RAW and RAI and that you misunderstand. So, we both think that we understand RAW and RAI and we'll just have to agree to disagree regarding the rest. That works for me! My buddies and I are all on the same page and we always discuss everything with one another, regardless of who is the DM and who is the player in the particular, which is ultimately what matters. Hopefully it works as well for you. Cheers!

Quote from Ancoulainn >>

Since I already addressed all of your points previously, all I can say is that, in the end, you think that you understand RAW and RAI and that I misunderstand and I think that I understand RAW and RAI and that you misunderstand. So, we both think that we understand RAW and RAI and will just have to agree to disagree regarding the rest. That works for me! My buddies and I are all on the same page and we always discuss everything with one another, regardless of who is the DM and who is the player in the particular, which is ultimately what matters. Hopefully it works as well for you. Cheers!

You haven't addressed them. You do you for your games, of course. However, given that I was in the middle of replying to your previous post before you deleted it, I did find an additional reference:

PHB Chapter 5 - Feats:

This chapter offers a collection of feats, which are special features not tied to a character class. A feat represents a talent or an area of expertise that gives a character special capabilities. It embodies training, experience, and abilities beyond what a class provides.

Feats can be received from Backgrounds, Class Levels, or, rarely, other methods (such as "advancement" after level 20). The feats you chose as a result of your Background, Class Levels 4, 8, 12, 16, and 19, or any other method, are not class features. When you get a Fighting Style, the Fighting Style feat you choose is not a class feature. If you choose the Lessons of the Old Ones Warlock Invocation, the Origin Feat is not class feature.

The Rhythm of the Game section calls out class features and feats as separate features and the feats chapter separates feats from class, explicitly, as well.

Potent Dragonmark is never a class feature, not if you take it at level 4, not if you take after getting 30,000 xp past level 20. The spells prepared by Potent Dragonmark are never prepared according to any classes Spellcasting Feature. Any feature, such as Wild Magic that depends on it being prepared according to a class's spellcasting feature will not trigger with a spell only prepared by Potent Dragonmark.

Is that silly? Yes. Is it raw? Also, yes. Do I intend to uphold RAW? No. I haven't run into multiclass spellcasting in 5.5 so I am running it as you are for now. However, I am recognizing that it is not RAW (and I am less concerned about balance since my players don't tend to optimize/abuse things). I don't disagree with your ruling, only with whether it is RAW or not.

Quote from Ancoulainn >>

As the 2014 DMG said

The D&D rules help you and the other players have a good time, but the rules aren’t in charge. You’re the DM, and you are in charge of the game.

 

This isn't in the 2024 DMG/PHB? I don't know that it's crucial for experienced players/DMs, but I still think a reminder of "rule 0" is good for newer players/DMs.