How to reverse the Balance card from a Deck of Many Things? [closed]

Question

At the end of the last story arc, I gave my players the chance to let their characters draw from a Deck of Many Things. I told them beforehand that this could mess up their characters and the whole campaign. They knew the risks and their characters knew too. Nonetheless, one character decided to draw a card, alongside with two NPCs.

And just as expected, the results were horrible and messed up the whole campaign. So the next story arc will focus on how the rest of the group deals with the problems. And they have a lot of problems now. But I found a way to link all those problems together, so they can go on an epic quest to fix everything.

Everything except one thing. A very important NPC (and member/sidekick of the party) drew the Balance card. I don’t like to define alignments for NPCs, so I decided that the card wouldn’t just change his alignment, but completely alter his personality. Before, he was funny, genuine and a little insecure. Now he’s serious, deceiving and confident. And the players hate it ^^. They want their old friend back.

So now I’m looking for a way to reverse the effect of the Balance card. I want to give the players the opportunity and chance to fix their friend. And this solution should be plausible and hard to achieve. I described the Deck of Many Things as this mystic and powerful artifact, which could change the world. So it shouldn’t be too easy to reverse its doings.

Are there any artifacts, spells, locations, events, deities, races, monsters or historical figures in D&D history associated with changing one's personality? We play D&D 5e in the Forgotten Realms Setting, but I’m open to suggestions from every edition or setting.

I know that there is a helmet that can change the alignment of its wearer, but I’m looking for a more permanent (and epic) solution. Some planes can affect one's alignment, but that’s not really what I’m looking for. And of course they could try to find another Deck of Many Things and draw the right card, but my players will never, ever draw a card from such a deck again ^^. (They’re not that stupid.)

Answer 1

The gods can likely reverse the effect of the Balance card

If you have at least a level 10 Cleric in your group, they can use Divine Intervention everyday until it works. Up until level 19, they only have at best a 19% chance to pull it off. However, a Level 20 Cleric can use it with 100% certainty.

Presumably, nobody in your group fits the bill, so you can make an adventure out of finding someone who can call upon the will of the gods to "cure" this card's effect.

There are ways to forcibly change someone's alignment

This answer lists the three ways you can do this by the book. The first two (magic items, planes) are things you have already discounted. The third involves a potential quest about looking for Slaadi. If a Blue Slaad knocks the NPC to 0 HP, they become Chaotic Neutral (and also a Red Slaad, but they don't need to know that).

The Balance card does not disappear from the Deck

Only the Joker cards poof out of existence permanently after they're drawn. All the other cards reappear in the deck. This means they can keep drawing from the one they already have until they find the same card again.

Once a card is drawn, it fades from existence. Unless the card is the Fool or the jester, the card reappears in the deck, making it possible to draw the same card twice.

Frame Challenge:

Do not reverse the effects of the card. They encouraged their NPC friend to pull from a deck that could have killed him, sent him to a prison where only a Wish spell could have brought him back, earned him the enmity of powerful devils, etc.

Make the party face the consequences of their actions. Allow them a "what have I done?" moment. They might hate the NPC now, but they made him that way. There is no Epic Quest to go and undo their mistakes: the real Epic Quest is in learning how to live with their decision of willingly putting a friend in harm's way for their amusement.

Answer 2

The wish spell could potentially reverse the effects, but maybe not. You have some leeway to partially make the problem go away, and partially make new problems for them to deal with.

Perhaps a stretch - Reincarnate spell. This creates a new body, different from resurrection which brings back the original.

Per DMG Page 162:

Balance. Your mind suffers a wrenching alteration causing your alignment to change.

If we decide that your "mind" is physical, we could say that having a new mind in a new body may not have this same wrenched alteration.

In the reincarnate case, the reincarnated being recalls its former life and experiences, but depending on DM ruling, the mind could be tied to the physical body:

The reincarnated creature recalls its former life and experiences. It retains the capabilities it had in its original form, except it exchanges its original race for the new one and changes its racial traits accordingly.

True resurrection Can make a new body if the old one is gone, which could follow the same as reincarnate.

In 3.5e there is Miracle for clerics, which is similar to Divine intervention in 5e, but Divine intervention seems to explicitly state that a Cleric spell's effect is appropriate. PHB page 59:

Beginning at 10th level, you can call on your deity to intervene on your behalf when your need is great.

Imploring your deity's aid requires you to use your action. Describe the assistance you seek, and roll percentile dice. If you roll a number equal to or lower than your cleric level, your deity intervenes. The DM chooses the nature of the intervention; the effect of any cleric spell or cleric domain spell would be appropriate. If your deity intervenes, you can't use this feature again for 7 days. Otherwise, you can use it again after you finish a Long Rest.

But your DM mileage may vary of course.