There is some significant problem with layers here. For starters the second ability doesn't do anything(as far at the card itself is concerned).
I don't think this reading is actually correct.
That would be true if the layers system operated on whole game states but it doesn't, it operates on objects. The calculations performed on each object can read (aiui) the surface game-state of any other object. So under that interpretation, the ability works fine.
I think you're misinterpreting user_938036's comment a little bit.
What he's saying is that giving the power and toughness boost to creature cards in graveyards won't affect the OP's card's power and toughness as it is defined by the characteristic-defining ability. The reason for this is indeed due to layers. What he isn't saying is that the creature cards' power and toughness in the graveyard aren't increased as the result of the resolution of the activated ability.
"Enchant Permanent" shouldn't be needed, as it only limits what the object can enchant, and causes it to fall off if the condition's not met.
Being an Aura is enough for all the actual workings.
You may want to review the rules for the enchant ability again. The enchant ability is absolutely required for the desired effect.
A triggered ability that appears in the text of another triggered ability or an activated ability means that the former is what's known as a delayed triggered ability. The delayed triggered ability won't do anything on its own; rather, it gets created when the triggered or activated ability encompassing it resolves.
Let's take the first card.
Suppose an instant or sorcery card enters my graveyard. The ability triggers, and so I choose to exile it. Since I choose to exile it, I return each other card exiled with Necrotic Spellplasm to my graveyard (not very relevant in this scenario). Then, because there are further instructions in the triggered ability, those are followed. Since it's a delayed triggered ability, a delayed triggered ability is set up that triggers whenever Spellplasm deals combat damage to a player. All is normal here; whenever Spellplasm deals combat damage to a player, I can cast a copy of the exiled card exactly once.
Then suppose a second instant or sorcery card enters my graveyard. The ability triggers, and so I choose to exile it. Since I choose to exile it, I return each other card exiled with Necrotic Spellplasm to my graveyard (the first instant or sorcery card exiled this way). Then, a delayed triggered ability will be created that triggers whenever Spellplasm deals combat damage to a player. However, note that the first delayed triggered ability still exists. This means, that if Spellplasm deals combat damage to a player, I will be able to cast a copy of my most recently-exiled instant or sorcery card twice.
This holds true in general. Assuming Spellplasm never leaves the battlefield for any reason, whenever the Nth instant or sorcery card is put into a graveyard and I choose to exile it, it makes it so that whenever Spellplasm deals combat damage to a player, I can cast a copy of that exiled instant or sorcery card up to N times.
Now let's look at the second card.
The second card is actually much more simple, in that the combat damage triggered ability is already there, and there aren't multiple generated copies to manage. This means that no matter how many instant or sorcery cards I exile with Spellplasm, I will only ever be able to cast a copy of the Nth exiled card once per combat damage event.
The first wording and third wording are fine. The only difference is whether or not you want an effect that checks whether a creature actually has trample returns true or false.
The second wording doesn't work, because the second line tries to be a spell ability that generates a continuous effect, but the resolution of enchantment spells have nothing to do with spell abilities, so that spell ability doesn't do anything.
I don't want any part of the interaction to be able to be stopped, so that the card can take something without giving something.
An "exchange" can only happen if what you are being given and what you are giving can both be given at the time the exchange is to occur. If you want taking something without giving something to be possible, then you can't use "exchange" as a game term. You would have to just use the word "simultaneously":
Choose target permanent you control and target permanent an opponent controls that shares a card type. Simultaneously, that opponent gains control of the permanent you control and you gain control of the permanent that opponent controls.
Note that other cards that use the "simultaneously" wording require that both targets remain legal as the effect is applied. This wording conveniently avoids that requirement, which means you are able to take without giving back. Change targeting restrictions as you see fit.
The comparison you bring up with the first ability doesn't quite hold. This is because life total changes can only happen with discrete events, i.e. being dealt damage, paying life, or gaining life. On the other hand, toughness changes can happen with both discrete events (such as effects from Giant Growth) or continuous effects (such as Glorious Anthem).
Specifically, your wording doesn't properly define what happens with effects that set power and toughness to specific values. This is true for both discrete effects (such as "Target creature becomes a...with base power and toughness 1/1") and for continuous effects (such as "Creatures you control are 1/1...").
The second ability doesn't prevent creatures from getting their toughness lowered to 0 or less through static abilities (such as "Creatures you don't control get -1/-1"). As mentioned before, static abilities don't cause events to happen, and since replacement effects only deal with events, they can't interact with toughness changes that aren't caused by events.
Without outright stating an impossibility, this kind of functionality can't really be achieved in Magic.
By definition, a replacement effect replaces some set of events A with some other set of events B. But due to how static abilities and continuous effects work, static abilities don't actually cause events to happen in a way that is compatible with replacement effects. Therefore, you can't use a replacement effect to nullify a static ability.
As far as MattTheGathering's wording is concerned, it works in the sense that it still allows for P/T-modifying counters to work. But it also allows for cards like Giant Growth to continue working as normal.
Due to the specificity of what you want, it would be best to spell out specifically what kinds of P/T modification are nullified and which aren't, either in rules text or in reminder text. I would go with something like the following:
Effects of spells and abilities can't increase or decrease a creature's power or toughness. (Its power and toughness can't be changed from its base power or toughness except by any counters on it.)
The above outright states that modifying P/T with things like Giant Growth or anthems are impossible game events. Among the sublayers in layer 7, the only layers that remain unchanged are the ones for CDA's, the one for base power and toughness setting, and the one for P/T modifications from counters.
Due to layers, permanents can't both "have changeling" and function the way you think that text does. Changeling is applied in layer 4, but ability-adding effects are applied in layer 6. By the time a given object gains changeling in layer 6, it will already have been too late for the changeling ability to apply in layer 4.
You will unfortunately need to say "have all creature types" instead of "have changeling".
"Whenever a player casts a spell or activates an ability, change its text by replacing all instances of "X" with 3."
Of the three I'm quoting here, this is the wording that most closely works.
Since you want this card to change the definition of any instance of "X" from whatever it may happen to be with 3, that just means you ignore the definition already printed on the card, and use 3 instead. This will work for Aether Bursts that are already on the stack; only three of the chosen targets will be returned to the hand, or if there were fewer than three targets in the first place, all targets will.
But as you said, this is a triggered ability, not a static ability, so it doesn't have the timing that you want.
Replace all instances of X in the text of spells and abilities you control with 3.
The issue with this is that "replace" already has a specific game meaning in Magic. As applied to replacement effects, the word "replace" only does something to an event that is about to happen (as in, all the requirements for that event to happen are there, but the event just hasn't happened yet). As applied to text-changing effects, it only applies to objects that already exist in the zone they need to be in (so it won't affect spells that are currently being cast). For continuous effects that need to apply to objects as they exist immediately after a zone change, the words "becomes" or "is" are used instead.
Furthermore, the term "text" applies to more than just the text that appears in the text box. It applies to all rules-relevant words and symbols on the card, which includes the text box, type line, name (for full name string matches, although no existing card does this yet), and, relevant to this discussion, mana cost. This means that by replacing "all instances of X in the text of spells and abilities you control with 3", any instances of X in the mana costs of spells you are currently casting and have already cast will also be affected.
As you state, this isn't what you want, so this wording doesn't work.
If a spell or ability you control would use X, it uses 3 instead.
This wording is formatted like a replacement effect. Replacement effects replace events with other events, by definition.
However, a spell or ability referring to one value for X or another isn't an event. It's an ongoing attribute that's true about the spell or ability itself. There is no discrete action that just "happens" here. Therefore, a replacement effect doesn't work here.
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My opinion is that you should have the card restrict values of X that can be chosen during the casting and activation of spells and abilities, too. But, referring to "rules text" specifically in the rules text of a spell or ability is extremely clunky, more so than referring to the "stack" in rules text. Given this, it would be optimal to not reference "rules text" in the text of whatever is written.
Because objects whose values of X are chosen for them (such as Fireball and Blaze) are so different than objects whose values of X are already predefined for them (such as Aether Burst), I wouldn't try to mash the modification of both kinds of objects' values of X into one single ability. Rather, I'd make one ability affect objects whose values of X are chosen for them, and one ability affect objects whose values of X are chosen by the player.
I wouldn't even bother trying to retroactively adjust values of X for spells and abilities that were already on the stack at the time this card enters the battlefield. The amount of objects this would actually affect is rather small, and to be honest, I don't think this added functionality is worth having extra card text on a card whose rules text would already be rather confusing to read.
While casting a spell, activating an ability, or putting a triggered ability you control onto the stack, you can't choose any value for X except for 3. (The same applies for other variable letters.)
Each instance of X on spells and abilities you control is 3 instead of its normal value.
Now, there's a loophole that I can think of at this point: What happens if I cast Blaze for X = 3, and my opponent gains control of my enchantment while Blaze is on the stack? The original intention would be that Blaze's X value would no longer be limited to just X = 3, and that I'd be able to choose whatever I want.
My answer for this is that this should be viewed as a feature of the card, rather than a violation of design intention; that is, the card should have some sort of "reward" for the opponent if they're able to steal the enchantment while a spell like Blaze is on the stack this way.
The rules don't currently support split cards that have permanent types on at least one half, but only because there is no rule that says how to treat a permanent represented by a split card. Under the strict interpretation of the rules as they are now, the card doesn't work.
However, the analogous rule does exist for the stack: For a spell represented by a split card on the stack, the spell is treated as though only the characteristics of the half being chosen exist. For fused spells, both halves' characteristics exist.
We can naturally extend this rule to say that permanents on the battlefield that were put there from the stack continue to have the same characteristics as it did when it was a spell. That is, it has only the characteristics of the half that was chosen when it was on the stack, or both if the spell on the stack was fused.
Things get a bit more confusing when considering reanimation effects, but not too much. Since this is completely uncharted territory, you are free to define the interaction as you wish. Personally, I would say that if a permanent represented by a split card is returned to the battlefield, the player returning the permanent chooses one half or the other, and only that half's characteristics will exist on the permanent.
As far as state-based actions are concerned, the previous posters actually have it reversed.
Any wording that uses "don't", "isn't", or "can't" outright ignores the relevant state-based actions that involve leaving the battlefield. For instance, indestructible completely ignores the lethal damage destruction state-based action, since it states that the affected object "isn't" destroyed by lethal damage. It doesn't cause the state-based action to be checked for that permanent, fail, and then check again. This means that your wording works, and will completely ignore any state-based actions that involve permanents leaving the battlefield.
On the other hand, any wording that involves a replacement effect that involves replacing leaving the battlefield with not leaving the battlefield (specifically this, not any other phrasing that also involves not leaving the battlefield) will actually still cause the relevant state-based action to be invoked, but the SBA will merely fail to invoke itself. The game will then see that SBA's need to be checked again, and will perform them again, and again, and so on. This will indeed cause the game to come to a draw.
A replacement effect that can't apply will just be ignored. It doesn't retroactively "unapply" itself by any means. This means that if the replacing event is impossible to perform, the effect just doesn't do anything. A permanent that enters the battlefield from the battlefield does not become a new object with no memory of its previous existence, simply because the rules don't say so. This means that the replacement effect that user_938036 mentioned won't actually work, because it will simply be ignored, and SBA's will need to be checked over and over again.
Out of all the cards featured here, a total of two cards work in the rules of Magic. Here are the main issues with these cards:
1) The jammed mechanic isn't worded correctly. You can't combine triggered abilities and replacement effects. They are mutually exclusive. "Double power", "double toughness", and "double converted mana cost" don't mean anything.
2) Many of the cards that ask for targets have no actual point in time where targets can be chosen. As a result, all text that requires targeting on those cards is effectively useless.
3) Kicker's (and multikicker's) linked abilities don't do anything on the majority of these cards.
4) The phrase "is jammed" doesn't mean anything.
5) Casy's Bat doesn't work properly in that it doesn't account for objects with multiple targets, where only one of which is the equipped creature. It needs a rework.
6) There's no such thing as "your opponent" in Magic.
7) Triple strike. Triple strike simply doesn't work without a insanely massive rules overhaul, which isn't worth it with what you're trying to do.
Also, while not really something that doesn't work in the rules, all multikicker costs are also kicker costs for the purposes of Gatling Gull.
A card's properties are its values. Properties seems more intuitive for reminder text so I went for that.
Neither of those have any rules meaning. You're going to need to use terms that actually have rules meaning, or your reminder text is just bad.
If a player experienced with the game's rules reads your reminder text and has no idea what the intent of the ability actually is, you need to change the reminder text.
And yes, it'll be P/T in addition to 1/1. Which means P+1/T+1. Same for mana costs.
That isn't how power, toughness, or mana costs work.
I didn't even notice the symbols. Geez.... I'm still trying to avoid posting a long tirade so I'll keep it short.
A lot of the design elements appear to be there because of other cards games, apparently without considering potential negative impact.
Let's take Yu-Gi-Oh Trap and Spell cards of which there are three types of the first and six types of the latter for a total of nine card types. These are functionally similar to instants, sorceries, and enchantment cards. Seven of the different types are denoted by six different symbols. A memory excercise but not insurmountable. Only marginally harder than trying to memorize the stupid tribute stars and far easier than the obscene rules for summoning creatures.
MTG lists 128 keywords. Menace is 702.118. WotC would be completely out of their minds if they created icons for just half of those keywords. Those symbols won't go away and worse, errata will undoubtedly be applied. Can you imagine?
AP "Ok this has a... so..."
NAP "No dude, that was errataed to be a ."
AP "Are you sure? Judge!"
Judge "lets see... Oracle says it is a ? Wait... what the **** does mean? **** it."
Yu-Gi-Oh is different in that the card type analogs you mention are put on the card only as symbols. The little lightning bolt icon next to the words "Spell Card" or "Trap Card" means that it's effectively the Yu-Gi-Oh equivalent of an instant, but there is no explicitly written word for that type on the card (Quick-Play, in this case).
The render would have both "flying" and a symbol denoting a pair of wings on the card. There's always the word "flying" to work off of if the player doesn't like looking at the equivalent symbol. No such luxury exists in Yu-Gi-Oh to my knowledge.
Of course, I don't necessarily agree with the idea of having the symbols on the card in the first place, but for what it's worth, the symbols hide exactly zero game information in the way that Yu-Gi-Oh's type symbols do.
I think you're misinterpreting user_938036's comment a little bit.
What he's saying is that giving the power and toughness boost to creature cards in graveyards won't affect the OP's card's power and toughness as it is defined by the characteristic-defining ability. The reason for this is indeed due to layers. What he isn't saying is that the creature cards' power and toughness in the graveyard aren't increased as the result of the resolution of the activated ability.
You may want to review the rules for the enchant ability again. The enchant ability is absolutely required for the desired effect.
Let's take the first card.
Suppose an instant or sorcery card enters my graveyard. The ability triggers, and so I choose to exile it. Since I choose to exile it, I return each other card exiled with Necrotic Spellplasm to my graveyard (not very relevant in this scenario). Then, because there are further instructions in the triggered ability, those are followed. Since it's a delayed triggered ability, a delayed triggered ability is set up that triggers whenever Spellplasm deals combat damage to a player. All is normal here; whenever Spellplasm deals combat damage to a player, I can cast a copy of the exiled card exactly once.
Then suppose a second instant or sorcery card enters my graveyard. The ability triggers, and so I choose to exile it. Since I choose to exile it, I return each other card exiled with Necrotic Spellplasm to my graveyard (the first instant or sorcery card exiled this way). Then, a delayed triggered ability will be created that triggers whenever Spellplasm deals combat damage to a player. However, note that the first delayed triggered ability still exists. This means, that if Spellplasm deals combat damage to a player, I will be able to cast a copy of my most recently-exiled instant or sorcery card twice.
This holds true in general. Assuming Spellplasm never leaves the battlefield for any reason, whenever the Nth instant or sorcery card is put into a graveyard and I choose to exile it, it makes it so that whenever Spellplasm deals combat damage to a player, I can cast a copy of that exiled instant or sorcery card up to N times.
Now let's look at the second card.
The second card is actually much more simple, in that the combat damage triggered ability is already there, and there aren't multiple generated copies to manage. This means that no matter how many instant or sorcery cards I exile with Spellplasm, I will only ever be able to cast a copy of the Nth exiled card once per combat damage event.
The second wording doesn't work, because the second line tries to be a spell ability that generates a continuous effect, but the resolution of enchantment spells have nothing to do with spell abilities, so that spell ability doesn't do anything.
An "exchange" can only happen if what you are being given and what you are giving can both be given at the time the exchange is to occur. If you want taking something without giving something to be possible, then you can't use "exchange" as a game term. You would have to just use the word "simultaneously":
Note that other cards that use the "simultaneously" wording require that both targets remain legal as the effect is applied. This wording conveniently avoids that requirement, which means you are able to take without giving back. Change targeting restrictions as you see fit.
Specifically, your wording doesn't properly define what happens with effects that set power and toughness to specific values. This is true for both discrete effects (such as "Target creature becomes a...with base power and toughness 1/1") and for continuous effects (such as "Creatures you control are 1/1...").
The second ability doesn't prevent creatures from getting their toughness lowered to 0 or less through static abilities (such as "Creatures you don't control get -1/-1"). As mentioned before, static abilities don't cause events to happen, and since replacement effects only deal with events, they can't interact with toughness changes that aren't caused by events.
By definition, a replacement effect replaces some set of events A with some other set of events B. But due to how static abilities and continuous effects work, static abilities don't actually cause events to happen in a way that is compatible with replacement effects. Therefore, you can't use a replacement effect to nullify a static ability.
As far as MattTheGathering's wording is concerned, it works in the sense that it still allows for P/T-modifying counters to work. But it also allows for cards like Giant Growth to continue working as normal.
Due to the specificity of what you want, it would be best to spell out specifically what kinds of P/T modification are nullified and which aren't, either in rules text or in reminder text. I would go with something like the following:
The above outright states that modifying P/T with things like Giant Growth or anthems are impossible game events. Among the sublayers in layer 7, the only layers that remain unchanged are the ones for CDA's, the one for base power and toughness setting, and the one for P/T modifications from counters.
You will unfortunately need to say "have all creature types" instead of "have changeling".
So far, none of the three wordings proposed actually work properly (or at least, to your intention).
Of the three I'm quoting here, this is the wording that most closely works.
Since you want this card to change the definition of any instance of "X" from whatever it may happen to be with 3, that just means you ignore the definition already printed on the card, and use 3 instead. This will work for Aether Bursts that are already on the stack; only three of the chosen targets will be returned to the hand, or if there were fewer than three targets in the first place, all targets will.
But as you said, this is a triggered ability, not a static ability, so it doesn't have the timing that you want.
The issue with this is that "replace" already has a specific game meaning in Magic. As applied to replacement effects, the word "replace" only does something to an event that is about to happen (as in, all the requirements for that event to happen are there, but the event just hasn't happened yet). As applied to text-changing effects, it only applies to objects that already exist in the zone they need to be in (so it won't affect spells that are currently being cast). For continuous effects that need to apply to objects as they exist immediately after a zone change, the words "becomes" or "is" are used instead.
Furthermore, the term "text" applies to more than just the text that appears in the text box. It applies to all rules-relevant words and symbols on the card, which includes the text box, type line, name (for full name string matches, although no existing card does this yet), and, relevant to this discussion, mana cost. This means that by replacing "all instances of X in the text of spells and abilities you control with 3", any instances of X in the mana costs of spells you are currently casting and have already cast will also be affected.
As you state, this isn't what you want, so this wording doesn't work.
This wording is formatted like a replacement effect. Replacement effects replace events with other events, by definition.
However, a spell or ability referring to one value for X or another isn't an event. It's an ongoing attribute that's true about the spell or ability itself. There is no discrete action that just "happens" here. Therefore, a replacement effect doesn't work here.
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My opinion is that you should have the card restrict values of X that can be chosen during the casting and activation of spells and abilities, too. But, referring to "rules text" specifically in the rules text of a spell or ability is extremely clunky, more so than referring to the "stack" in rules text. Given this, it would be optimal to not reference "rules text" in the text of whatever is written.
Because objects whose values of X are chosen for them (such as Fireball and Blaze) are so different than objects whose values of X are already predefined for them (such as Aether Burst), I wouldn't try to mash the modification of both kinds of objects' values of X into one single ability. Rather, I'd make one ability affect objects whose values of X are chosen for them, and one ability affect objects whose values of X are chosen by the player.
I wouldn't even bother trying to retroactively adjust values of X for spells and abilities that were already on the stack at the time this card enters the battlefield. The amount of objects this would actually affect is rather small, and to be honest, I don't think this added functionality is worth having extra card text on a card whose rules text would already be rather confusing to read.
Each instance of X on spells and abilities you control is 3 instead of its normal value.
Now, there's a loophole that I can think of at this point: What happens if I cast Blaze for X = 3, and my opponent gains control of my enchantment while Blaze is on the stack? The original intention would be that Blaze's X value would no longer be limited to just X = 3, and that I'd be able to choose whatever I want.
My answer for this is that this should be viewed as a feature of the card, rather than a violation of design intention; that is, the card should have some sort of "reward" for the opponent if they're able to steal the enchantment while a spell like Blaze is on the stack this way.
However, the analogous rule does exist for the stack: For a spell represented by a split card on the stack, the spell is treated as though only the characteristics of the half being chosen exist. For fused spells, both halves' characteristics exist.
We can naturally extend this rule to say that permanents on the battlefield that were put there from the stack continue to have the same characteristics as it did when it was a spell. That is, it has only the characteristics of the half that was chosen when it was on the stack, or both if the spell on the stack was fused.
Things get a bit more confusing when considering reanimation effects, but not too much. Since this is completely uncharted territory, you are free to define the interaction as you wish. Personally, I would say that if a permanent represented by a split card is returned to the battlefield, the player returning the permanent chooses one half or the other, and only that half's characteristics will exist on the permanent.
Any wording that uses "don't", "isn't", or "can't" outright ignores the relevant state-based actions that involve leaving the battlefield. For instance, indestructible completely ignores the lethal damage destruction state-based action, since it states that the affected object "isn't" destroyed by lethal damage. It doesn't cause the state-based action to be checked for that permanent, fail, and then check again. This means that your wording works, and will completely ignore any state-based actions that involve permanents leaving the battlefield.
On the other hand, any wording that involves a replacement effect that involves replacing leaving the battlefield with not leaving the battlefield (specifically this, not any other phrasing that also involves not leaving the battlefield) will actually still cause the relevant state-based action to be invoked, but the SBA will merely fail to invoke itself. The game will then see that SBA's need to be checked again, and will perform them again, and again, and so on. This will indeed cause the game to come to a draw.
A replacement effect that can't apply will just be ignored. It doesn't retroactively "unapply" itself by any means. This means that if the replacing event is impossible to perform, the effect just doesn't do anything. A permanent that enters the battlefield from the battlefield does not become a new object with no memory of its previous existence, simply because the rules don't say so. This means that the replacement effect that user_938036 mentioned won't actually work, because it will simply be ignored, and SBA's will need to be checked over and over again.
1) The jammed mechanic isn't worded correctly. You can't combine triggered abilities and replacement effects. They are mutually exclusive. "Double power", "double toughness", and "double converted mana cost" don't mean anything.
2) Many of the cards that ask for targets have no actual point in time where targets can be chosen. As a result, all text that requires targeting on those cards is effectively useless.
3) Kicker's (and multikicker's) linked abilities don't do anything on the majority of these cards.
4) The phrase "is jammed" doesn't mean anything.
5) Casy's Bat doesn't work properly in that it doesn't account for objects with multiple targets, where only one of which is the equipped creature. It needs a rework.
6) There's no such thing as "your opponent" in Magic.
7) Triple strike. Triple strike simply doesn't work without a insanely massive rules overhaul, which isn't worth it with what you're trying to do.
Also, while not really something that doesn't work in the rules, all multikicker costs are also kicker costs for the purposes of Gatling Gull.
You may want to read the rules entry you're quoting again.
Neither of those have any rules meaning. You're going to need to use terms that actually have rules meaning, or your reminder text is just bad.
If a player experienced with the game's rules reads your reminder text and has no idea what the intent of the ability actually is, you need to change the reminder text.
That isn't how power, toughness, or mana costs work.
Yu-Gi-Oh is different in that the card type analogs you mention are put on the card only as symbols. The little lightning bolt icon next to the words "Spell Card" or "Trap Card" means that it's effectively the Yu-Gi-Oh equivalent of an instant, but there is no explicitly written word for that type on the card (Quick-Play, in this case).
The render would have both "flying" and a symbol denoting a pair of wings on the card. There's always the word "flying" to work off of if the player doesn't like looking at the equivalent symbol. No such luxury exists in Yu-Gi-Oh to my knowledge.
Of course, I don't necessarily agree with the idea of having the symbols on the card in the first place, but for what it's worth, the symbols hide exactly zero game information in the way that Yu-Gi-Oh's type symbols do.