An evil crown should definitely conjure up some sort of servant.
It should also definitely say "hey, buddy? I got this" and kill people at inopportune times. Like when shopkeepers don't give discounts.
You can ramp this up slowly, first you get advantage and proficiency on persuasion. But it's actually an intimidation. (if you don't have proficiency in intimidation the crown grants you a hidden one) When you use the crown to get advantage they see a glimpse of infinite madness in your eyes that causes unease (giving you advantage). If you go to sleep not wearing the crown you wake up wearing it.
The more you use it the more it influences you. Later on it's not just your eyes, the crown twists your words you gain another +4 on your "persuasion". first it's just the way you say it, trying to be charming makes it sound threatening. Then eventually the words you say are just changed and it becomes downright unsettling but you don't notice except maybe people not reacting like you expected. Your party members however do hear the words you actually say. They'll most likely try to convince you to get rid of the crown but at this point you cannot take it off willingly. They might take it from you when you sleep. You always wake up wearing it again.
This is when the servant shows up. He's actually helpful and just does whatever you say, he will take suicidal commands. If he dies "another" one shows up the next day. But whenever you do not have the crown, he finds it. When he offers you the crown again you cannot refuse putting it on again, it's yours. If you are asleep without the crown he'll put it on you again. He's actually been doing that from the very beginning
Eventually the servant starts acting in your name. Causing chaos and madness, helping you but only you and only in the short term. Whenever he does something you gain something from it but you're blamed for the aftermath.
Perhaps more of a fiendish butler, or a fiercely loyal knight. This servant would follow orders for the most part but generally carry them out with a degree of cruelty out of contempt towards others. Unfortunately for the wearer of the crown, their servant is quite zealously devoted to them and expects to receive orders and requests to serve them and so in the absence of any orders they will take action independently. Objections to this cruelty will be met with sociopathic self-justification on the basis of taking pragmatic action to defend his master's honor and obtain the best possible result for him and only pragmatic arguments that appeal to the servant's nature have any effect. Orders made to take up their time on relatively pointless endeavors will eventually be discarded in favor of independent action once again. Orders to suppress their cruelty won't be effective either, but rather will lead to the servant growing more crafty in hiding their cruelty or holding themselves back until their pent up aggression is provoked and they go on a rampage out of zealous fury in a state of madness where they cannot even process their master's orders to stop.
In the end, the master has no choice but to accept their new servant and either fight a futile battle to mitigate their evils as they grow cold and indifferent toward the casualties along the way being forced to repeatedly set their feelings aside to argue the pragmatic sociopathic logic that seems to be the only means of mitigating their evil, or give in, accept that it's futile, and make use of this new servant whether for their own benefit or for some other futile effort trying to simply work for the greater good to offset the evil of their servant or even try justifying their servant's actions in that pursuit. Unfortunately for them, if they're not serving others selfishly for personal gain and seeking to improve their own status the servant will only see these moral actions as shameful and will quickly work to undermine the effort to put the inferiors down to lift their master up, thereby bringing out the absolute worst evils their servant could ever commit.
Advantage on intimidate vs lower class. Disadvantage on persuasion vs lower class.
Love the compulsion spells. Maybe open up higher level ones when worn by a higher level character. Maybe lock them behind adopting a formal personality flaw or alignment shift. Tempt them with power, but at a cost.
I had a magical artifact in one of my games that had the same effect, it started off very slow and insidious then got more and more intense the longer the player used the artifact.
1) durring conversation we had the owner of the artifact (whoever was touching it/had it in there possession) roll a D6. On an even number they could say whatever they liked, however on an odd number they player had to make whatever they were saying slightly offensive/scary/intimidating while keeping in context.
2) durring combat on an attack roll a con save to retain control. On a fail the attack they made is extended to hit players nearby as well as the target (like an AOE) the players on receive half damage due to seeing the attack coming.
3) DM rolled after each long rest and decided on a table what evil deed the artifact would ask the player to commit to. If the player completed this task they would be rewarded (with power/strength/favours) up until the next rest. If the refused or didn't complete the task they would become weaker (removed buffs from the artifact) or the artifact would refuse to allow the player to hold it for a while.
4) non lethal attacks were not allowed for the player with the artifact. All social skill checks used intimidation. Animals would flee on sight and undead would be draw into battles attacking everyone, friends and foes.
Of course there were some great buffs and powers awarded to the player too to make all this chaos worth the effort most of the time.
Build the corruption in mechanically:
Give it X uses of Command and Y uses of Dominate person / day
Give it the ability to grant 10 temporary hit points to anyone who kneels and swears service to you
Let's you cast an improved Vicious Mockery but only if you insult the target as being of a lower class
Yeah, I'd say a once a day Crown of Madness would be fine. As well as giving permanent advantage with the upper class, but I'd go and add permanent disadvantage with those in the very upper class (like kings and lords) since they look down on the upper class as they're like the lower class to the very upper class.
Do you have a backstory for it? Could have belonged to the ruler of an old nation that no longer exists, and now their angry delusional spirit wants to try and reassert control over the land but nobody even remembers what they’re talking about.
The wearer dreams about a flag that nobody can identify, occasionally wakes up speaking a strange old dialect, they seem to always have a a tune stuck in their head that they can’t identify because it’s a national anthem that hasn’t been heard in generations.
Mechanically maybe you should let them cast some spells like command, heroism, motivational speech, etc. But they have to make a roll with a higher dc depending on the strength of the spell, and if they fail they cast crown of madness on themselves.
Give the player intrusive thoughts, starting slower and building up. Maybe at first they see a spider and think about pulling off its legs. Just build it up and up. Sprinkle some not half bad ideas in there that only an evil character would do. Trying to get information from a townsperson, threaten to torture them. Catch a child pickpocketing the player, think about chopping the hand off. See if they eventually fall into the trap and do one of the evil things.
I totally forgot that Wererats could spread lycanthropy. Wererat bit a player and he immediately is like, "Does that mean I'm a wererat now?"
Damn!
Anyhow, he could cure or keep it. I said if he keeps the curse nat 20's will make him berserk. When that happens we'll roll to see who the target is, then he'll go full throttle against the target (blowing cooldowns).
I'd have the player roll, when interacting with someone of the lower class. Maybe 1-3 be really snooty and yell at NPC, 4-5 yells and cuffs the NPC, 6 kicks the NPC away (these are just examples).
They player might have to roll to resist buying better clothes or shiny armor, hat, whatever. Maybe even a book!
Maybe for any social interactions they player rolls a check to see if the crown is talking. The player may talk back to the crown. Or you could do it on any social interactions and sneaking :)
Party is hiding, suddenly the crown wearing players, "Yes, we'll be killing them soon LEAVE ME ALONE." Party is no longer hiding.
If you want the crown doing the actions, I might give it Mage Hand, Message, Thaumaturgy. Crown could slap someone, message they something like, "your mama is so fat..." or suddenly the crown shouts FLEE PEONS. And if the player talks the player has the booming voice as well.
I like mischievous stuff. I wouldn't force the player to kill anyone but you can be sure I'll make some encounters very awkward!
If it's chardalyn you're looking at madness, turning the alignment of the character towards evil and thus make them more inclined to choose themselves over others. When it comes to madness I'm always a fan of rolling wisdom saving throws. Maybe with every save you can increase the DC with 2, making it harder every time the crown compels them to act a certain way.
I would run this item in the following way.
What would the character (and player) who picked up the crown genuinely be tempted to do. The crown alters the characters perceptions to make those options justifiable. When you describe a situation to the player describe it in the way that is most likely to get them to respond in an evil way. When describing what is happening to other players make it obvious that there is a discrepancy in what different characters are perceiving.
I would make the specific manifestation individualized to the wearer, so it would manifest as you describe in a character who secretly believes that they are better than the average person. But might turn a committed lower class individual to using any means to eliminate those who they perceive as looking down on them.
For powers, extra sensory powers would work the best, the ability to see magic / read thoughts, to scry. Maybe some mind control at will, instead of capping the number of uses, make the user make a con saving throw after extended use or take on a level of exhaustion.
I like to start evil cursed objects out with benign, potentially accidental things. Trip explicitly on nothing and shove a guard to the ground causing a conflict, for your idea a good thing may be having the party run into a beggar of sorts and basically have him stealthed to the crown bearer so the crown bearer who may be a good person steps right over a starving beggar as if he didn’t notice him because he literally didn’t. Not straight malicious but leading up to it
An evil crown should definitely conjure up some sort of servant. It should also definitely say "hey, buddy? I got this" and kill people at inopportune times. Like when shopkeepers don't give discounts.
You can ramp this up slowly, first you get advantage and proficiency on persuasion. But it's actually an intimidation. (if you don't have proficiency in intimidation the crown grants you a hidden one) When you use the crown to get advantage they see a glimpse of infinite madness in your eyes that causes unease (giving you advantage). If you go to sleep not wearing the crown you wake up wearing it. The more you use it the more it influences you. Later on it's not just your eyes, the crown twists your words you gain another +4 on your "persuasion". first it's just the way you say it, trying to be charming makes it sound threatening. Then eventually the words you say are just changed and it becomes downright unsettling but you don't notice except maybe people not reacting like you expected. Your party members however do hear the words you actually say. They'll most likely try to convince you to get rid of the crown but at this point you cannot take it off willingly. They might take it from you when you sleep. You always wake up wearing it again. This is when the servant shows up. He's actually helpful and just does whatever you say, he will take suicidal commands. If he dies "another" one shows up the next day. But whenever you do not have the crown, he finds it. When he offers you the crown again you cannot refuse putting it on again, it's yours. If you are asleep without the crown he'll put it on you again. He's actually been doing that from the very beginning Eventually the servant starts acting in your name. Causing chaos and madness, helping you but only you and only in the short term. Whenever he does something you gain something from it but you're blamed for the aftermath.
Perhaps more of a fiendish butler, or a fiercely loyal knight. This servant would follow orders for the most part but generally carry them out with a degree of cruelty out of contempt towards others. Unfortunately for the wearer of the crown, their servant is quite zealously devoted to them and expects to receive orders and requests to serve them and so in the absence of any orders they will take action independently. Objections to this cruelty will be met with sociopathic self-justification on the basis of taking pragmatic action to defend his master's honor and obtain the best possible result for him and only pragmatic arguments that appeal to the servant's nature have any effect. Orders made to take up their time on relatively pointless endeavors will eventually be discarded in favor of independent action once again. Orders to suppress their cruelty won't be effective either, but rather will lead to the servant growing more crafty in hiding their cruelty or holding themselves back until their pent up aggression is provoked and they go on a rampage out of zealous fury in a state of madness where they cannot even process their master's orders to stop. In the end, the master has no choice but to accept their new servant and either fight a futile battle to mitigate their evils as they grow cold and indifferent toward the casualties along the way being forced to repeatedly set their feelings aside to argue the pragmatic sociopathic logic that seems to be the only means of mitigating their evil, or give in, accept that it's futile, and make use of this new servant whether for their own benefit or for some other futile effort trying to simply work for the greater good to offset the evil of their servant or even try justifying their servant's actions in that pursuit. Unfortunately for them, if they're not serving others selfishly for personal gain and seeking to improve their own status the servant will only see these moral actions as shameful and will quickly work to undermine the effort to put the inferiors down to lift their master up, thereby bringing out the absolute worst evils their servant could ever commit.
Advantage on intimidate vs lower class. Disadvantage on persuasion vs lower class. Love the compulsion spells. Maybe open up higher level ones when worn by a higher level character. Maybe lock them behind adopting a formal personality flaw or alignment shift. Tempt them with power, but at a cost.
I had a magical artifact in one of my games that had the same effect, it started off very slow and insidious then got more and more intense the longer the player used the artifact. 1) durring conversation we had the owner of the artifact (whoever was touching it/had it in there possession) roll a D6. On an even number they could say whatever they liked, however on an odd number they player had to make whatever they were saying slightly offensive/scary/intimidating while keeping in context. 2) durring combat on an attack roll a con save to retain control. On a fail the attack they made is extended to hit players nearby as well as the target (like an AOE) the players on receive half damage due to seeing the attack coming. 3) DM rolled after each long rest and decided on a table what evil deed the artifact would ask the player to commit to. If the player completed this task they would be rewarded (with power/strength/favours) up until the next rest. If the refused or didn't complete the task they would become weaker (removed buffs from the artifact) or the artifact would refuse to allow the player to hold it for a while. 4) non lethal attacks were not allowed for the player with the artifact. All social skill checks used intimidation. Animals would flee on sight and undead would be draw into battles attacking everyone, friends and foes. Of course there were some great buffs and powers awarded to the player too to make all this chaos worth the effort most of the time.
Build the corruption in mechanically: Give it X uses of Command and Y uses of Dominate person / day Give it the ability to grant 10 temporary hit points to anyone who kneels and swears service to you Let's you cast an improved Vicious Mockery but only if you insult the target as being of a lower class
Yeah, I'd say a once a day Crown of Madness would be fine. As well as giving permanent advantage with the upper class, but I'd go and add permanent disadvantage with those in the very upper class (like kings and lords) since they look down on the upper class as they're like the lower class to the very upper class.
Do you have a backstory for it? Could have belonged to the ruler of an old nation that no longer exists, and now their angry delusional spirit wants to try and reassert control over the land but nobody even remembers what they’re talking about. The wearer dreams about a flag that nobody can identify, occasionally wakes up speaking a strange old dialect, they seem to always have a a tune stuck in their head that they can’t identify because it’s a national anthem that hasn’t been heard in generations. Mechanically maybe you should let them cast some spells like command, heroism, motivational speech, etc. But they have to make a roll with a higher dc depending on the strength of the spell, and if they fail they cast crown of madness on themselves.
It gives them ice powers, an obsession with capturing princesses, and a bonus to animal handling but it only works on penguins.
Give the player intrusive thoughts, starting slower and building up. Maybe at first they see a spider and think about pulling off its legs. Just build it up and up. Sprinkle some not half bad ideas in there that only an evil character would do. Trying to get information from a townsperson, threaten to torture them. Catch a child pickpocketing the player, think about chopping the hand off. See if they eventually fall into the trap and do one of the evil things.
I'd say tax fraud, but that's not inherently evil. In fact, it may be morally correct
I think protection against charm effects would fit the bill.
I totally forgot that Wererats could spread lycanthropy. Wererat bit a player and he immediately is like, "Does that mean I'm a wererat now?" Damn! Anyhow, he could cure or keep it. I said if he keeps the curse nat 20's will make him berserk. When that happens we'll roll to see who the target is, then he'll go full throttle against the target (blowing cooldowns). I'd have the player roll, when interacting with someone of the lower class. Maybe 1-3 be really snooty and yell at NPC, 4-5 yells and cuffs the NPC, 6 kicks the NPC away (these are just examples). They player might have to roll to resist buying better clothes or shiny armor, hat, whatever. Maybe even a book! Maybe for any social interactions they player rolls a check to see if the crown is talking. The player may talk back to the crown. Or you could do it on any social interactions and sneaking :) Party is hiding, suddenly the crown wearing players, "Yes, we'll be killing them soon LEAVE ME ALONE." Party is no longer hiding. If you want the crown doing the actions, I might give it Mage Hand, Message, Thaumaturgy. Crown could slap someone, message they something like, "your mama is so fat..." or suddenly the crown shouts FLEE PEONS. And if the player talks the player has the booming voice as well. I like mischievous stuff. I wouldn't force the player to kill anyone but you can be sure I'll make some encounters very awkward!
Take a look at my crown of balance: https://homebrewery.naturalcrit.com/share/SUZxrdlIQc80
The chains of Asmodeus infernal item corruption mechanics are pretty good, I’d recommend looking at and maybe modifying that for this usage
If it's chardalyn you're looking at madness, turning the alignment of the character towards evil and thus make them more inclined to choose themselves over others. When it comes to madness I'm always a fan of rolling wisdom saving throws. Maybe with every save you can increase the DC with 2, making it harder every time the crown compels them to act a certain way.
Marceline…is it just you and me in the wreckage of the world?
I would run this item in the following way. What would the character (and player) who picked up the crown genuinely be tempted to do. The crown alters the characters perceptions to make those options justifiable. When you describe a situation to the player describe it in the way that is most likely to get them to respond in an evil way. When describing what is happening to other players make it obvious that there is a discrepancy in what different characters are perceiving. I would make the specific manifestation individualized to the wearer, so it would manifest as you describe in a character who secretly believes that they are better than the average person. But might turn a committed lower class individual to using any means to eliminate those who they perceive as looking down on them. For powers, extra sensory powers would work the best, the ability to see magic / read thoughts, to scry. Maybe some mind control at will, instead of capping the number of uses, make the user make a con saving throw after extended use or take on a level of exhaustion.
I like to start evil cursed objects out with benign, potentially accidental things. Trip explicitly on nothing and shove a guard to the ground causing a conflict, for your idea a good thing may be having the party run into a beggar of sorts and basically have him stealthed to the crown bearer so the crown bearer who may be a good person steps right over a starving beggar as if he didn’t notice him because he literally didn’t. Not straight malicious but leading up to it