I've been kicking around an idea for a campaign. I don't see myself getting a game together anytime soon, but I thought I'd at least see what people thought about this one aspect.
Included in it would be a spell that a powerful Demodand used (whether it made it itself or learned it, is currently unknown). The spell would need to be homebrewed, and I suspect it'd be a 9th level enchantment spell. Its effects would be similar to what Golbez was subjected to in Final Fantasy IV (and he in turn used on Kain), or what Babidi used in Dragon Ball Z on his minions.
Shackles of Agathys: The spell causes a sapient target to become a purely-evil version of itself, but loyal to the caster. If the target has any evil in their heart, they must make a Charisma saving throw, or else have their inner evil magnified until it is all-consuming; outsiders have Advantage on their saving throw, and the spell cannot affect undead, non-sapient creatures, or creatures devoid of evil. If the caster succeeds, they may mark their thrall with a simple rune, shape, or alphanumeric character.
While under the spell's influence, the target gets a +2 bonus to their Strength, Dexterity, and Constitution, but will be compelled to obey the caster's commands; if ordered to intentionally self-harm, the victim may attempt a Wisdom saving throw to refuse or twist the command's meaning. If not directly commanded by the caster, the victim will either continue to work towards their master's goals; if such goals are unknown or the caster has not given any information that the victim would be able to use to pursue them the thrall may pursue nefarious ends of its own, so long as they do not interfere with the caster's goals.
The target remains under the caster's control until either released by the caster, the caster is slain, a Wish is used to attempt to break the spell, or a Dispel Magic upcast as a 9th-level spell is used to attempt to break it (the dispeller must still beat a DC 29 + caster's spellcasting modifier). The spell persists through death, and the victim will return under the caster's control if resurrected. If a Dispel Magic comes within 4 points of success, the victim may reattempt their Charisma save to break free with Disadvantage (outsiders roll normally). If someone has successfully saved against this spell, they are immune to any repeat castings by the same caster.
As the spell does not require the caster's concentration, they may attempt to enthrall more than one target; being enthralled does not preclude someone from casting this spell on another, though they may not cast it on whoever cast it on them. Multiple thralls to the same caster are not necessarily loyal to each other, and even if ordered to work together, thralls may attempt to betray or undermine one another.
There's a lot of stuff going on here that suffers from either not being functionally defined in the rules, or just generally a bit vague. I'll attempt to highlight what I mean:
Shackles of Agathys: The spell causes a sapient target
The mechanics of the game don't define 'sapient'. You'll need to define this; minimum int score? Creature type? Not a certain creature type. Maybe make it so beasts, monstrosities, undead and constructs aren't affected?
to become a purely-evil version of itself, but loyal to the caster. If the target has any evil in their heart, they must make a Charisma saving throw, or else have their inner evil magnified until it is all-consuming;
How are you going to mechanically quantify/define 'any evil in their heart'? The only mechanic this could parallel is alignment and even then that doesn't work; even a lawful good creature could have some evil in its heart, depending on how you define it. This section might be worth removing altogether.
outsiders have Advantage on their saving throw, and the spell cannot affect undead, non-sapient creatures, or creatures devoid of evil. If the caster succeeds, they may mark their thrall with a simple rune, shape, or alphanumeric character.
What does 'outsiders' mean? That's not a mechanical term in D&D.
While under the spell's influence, the target gets a +2 bonus to their Strength, Dexterity, and Constitution,
Score or modifier? Big difference between the two.
but will be compelled to obey the caster's commands; if ordered to intentionally self-harm, the victim may attempt a Wisdom saving throw to refuse or twist the command's meaning.
Refuse or twist seems redundant, why would you twist when you can just refuse?
If not directly commanded by the caster, the victim will either continue to work towards their master's goals; if such goals are unknown or the caster has not given any information that the victim would be able to use to pursue them the thrall may pursue nefarious ends of its own, so long as they do not interfere with the caster's goals.
What does 'nefarious ends of its own' mean? What does the thrall do if it doesn't have "nefarious ends" to work towards?
The target remains under the caster's control until either released by the caster, the caster is slain, a Wish is used to attempt to break the spell, or a Dispel Magic upcast as a 9th-level spell is used to attempt to break it (the dispeller must still beat a DC 29 + caster's spellcasting modifier).
Upcast isn't a game term. You'd want something like "or Dispel Magic is cast on the target using a 9th level spell slot." Also that's not how the DC on Dispel Magic works, it's normally 10 + the spells level. Also 29 + anything is absurdly high.
The spell persists through death, and the victim will return under the caster's control if resurrected. If a Dispel Magic comes within 4 points of success, the victim may reattempt their Charisma save to break free with Disadvantage (outsiders roll normally).
The game doesn't refer to 'points of success', instead usually saying something like "if you fail the check by 5 or more". 4 is a very odd number to choose as well and this manner of repeating the save is very clunky. I think this needs simplifying.
If someone has successfully saved against this spell, they are immune to any repeat castings by the same caster.
Permanent immunity is a bit of a headache to track. Most spells and abilities go with just 24 hours to avoid complexity.
As the spell does not require the caster's concentration,
You don't need to specify this, spells by default don't need concentration, and say so if they do.
they may attempt to enthrall more than one target; being enthralled does not preclude someone from casting this spell on another, though they may not cast it on whoever cast it on them. Multiple thralls to the same caster are not necessarily loyal to each other, and even if ordered to work together, thralls may attempt to betray or undermine one another
Unlimited repeat casting is absurdly strong, unless this was a 9th level spell. Even so, there should be some kind of cap.
I've been kicking around an idea for a campaign. I don't see myself getting a game together anytime soon, but I thought I'd at least see what people thought about this one aspect.
Included in it would be a spell that a powerful Demodand used (whether it made it itself or learned it, is currently unknown). The spell would need to be homebrewed, and I suspect it'd be a 9th level enchantment spell. Its effects would be similar to what Golbez was subjected to in Final Fantasy IV (and he in turn used on Kain), or what Babidi used in Dragon Ball Z on his minions.
Shackles of Agathys: The spell causes a sapient target to become a purely-evil version of itself, but loyal to the caster. If the target has any evil in their heart, they must make a Charisma saving throw, or else have their inner evil magnified until it is all-consuming; outsiders have Advantage on their saving throw, and the spell cannot affect undead, non-sapient creatures, or creatures devoid of evil. If the caster succeeds, they may mark their thrall with a simple rune, shape, or alphanumeric character.
While under the spell's influence, the target gets a +2 bonus to their Strength, Dexterity, and Constitution, but will be compelled to obey the caster's commands; if ordered to intentionally self-harm, the victim may attempt a Wisdom saving throw to refuse or twist the command's meaning. If not directly commanded by the caster, the victim will either continue to work towards their master's goals; if such goals are unknown or the caster has not given any information that the victim would be able to use to pursue them the thrall may pursue nefarious ends of its own, so long as they do not interfere with the caster's goals.
The target remains under the caster's control until either released by the caster, the caster is slain, a Wish is used to attempt to break the spell, or a Dispel Magic upcast as a 9th-level spell is used to attempt to break it (the dispeller must still beat a DC 29 + caster's spellcasting modifier). The spell persists through death, and the victim will return under the caster's control if resurrected. If a Dispel Magic comes within 4 points of success, the victim may reattempt their Charisma save to break free with Disadvantage (outsiders roll normally). If someone has successfully saved against this spell, they are immune to any repeat castings by the same caster.
As the spell does not require the caster's concentration, they may attempt to enthrall more than one target; being enthralled does not preclude someone from casting this spell on another, though they may not cast it on whoever cast it on them. Multiple thralls to the same caster are not necessarily loyal to each other, and even if ordered to work together, thralls may attempt to betray or undermine one another.
Any feedback is welcome.
There's a lot of stuff going on here that suffers from either not being functionally defined in the rules, or just generally a bit vague. I'll attempt to highlight what I mean:
The mechanics of the game don't define 'sapient'. You'll need to define this; minimum int score? Creature type? Not a certain creature type. Maybe make it so beasts, monstrosities, undead and constructs aren't affected?
How are you going to mechanically quantify/define 'any evil in their heart'? The only mechanic this could parallel is alignment and even then that doesn't work; even a lawful good creature could have some evil in its heart, depending on how you define it. This section might be worth removing altogether.
What does 'outsiders' mean? That's not a mechanical term in D&D.
Score or modifier? Big difference between the two.
Refuse or twist seems redundant, why would you twist when you can just refuse?
What does 'nefarious ends of its own' mean? What does the thrall do if it doesn't have "nefarious ends" to work towards?
Upcast isn't a game term. You'd want something like "or Dispel Magic is cast on the target using a 9th level spell slot." Also that's not how the DC on Dispel Magic works, it's normally 10 + the spells level. Also 29 + anything is absurdly high.
The game doesn't refer to 'points of success', instead usually saying something like "if you fail the check by 5 or more". 4 is a very odd number to choose as well and this manner of repeating the save is very clunky. I think this needs simplifying.
Permanent immunity is a bit of a headache to track. Most spells and abilities go with just 24 hours to avoid complexity.
You don't need to specify this, spells by default don't need concentration, and say so if they do.
Unlimited repeat casting is absurdly strong, unless this was a 9th level spell. Even so, there should be some kind of cap.
I hope this feedback helps
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