The Adventuring Curse (5e Curse)
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The Adventuring Curse
(DM Warning: This curse may not be suitable for normal gameplay, and may break the game if not only used on NPCs, such as Shawn Spellblade.)
Most curses are designed by someone who solely seeks to make another person suffer a fate worse than death. They tend to focus so much on the negative effects of a curse that unforeseen and very powerful benefits can occur that are caused by the very detriments meant to make the victim suffer. This was something found out and known by Teresa Rose Maddox, an Awakened Seer trying to bring to life a very old prophecy. By focusing on the positive effects the curse brings, she custom built a curse that would prevent the death of the victim, and guarantee that they continuously must grow stronger to overcome adversity. All of this was done to Shawn Spellblade, cursing him before he was even born to ensure that he would always win in the end, if treated properly in the way that only a Seer can. As the inventor of this curse and the only creature that knows it, the information would have to be pried out from her mind in order to appear elsewhere, something she took extreme care to ensure was impossible. Firstly, she doesn't remember how to cast the curse (she erased her own memory), doesn't know how to cure it (Designed it to be literally incurable and ingrained into the very soul of the cursed), and has told no one, not even Shawn Spellblade himself of the curse. All of these steps were taken to ensure it could not be used or cured, so that Shawn would grow strong enough to defeat The Devourer of Worlds permanently and fulfill that prophecy. This Devourer is very different from the normal one in D&D lore, and shockingly Shawn himself has seemingly befriended the entity.
A creature cannot contract this curse on accident, as its structured nature and spell-based delivery means it's likely been on a creature since birth, or as a result of failing the saving throw against a specialized, epic magic version of the bestow curse spell, made to be permanent and impossible to dispel (By normal means). Attempting to cast this specialized version without making it permanent and impossible to dispel (By normal means) causes the spell to fail.
The Adventuring Curse causes the victim to constantly be in conflict, which must be at least a level of danger that the victim has difficulty handling. However, because a creature that is dead is simply almost never going to fall under conflict, this forces the victim to survive any conflict levied against it. The curse is capable of altering reality if required to attract conflict to its bearer, or to allow the victim to survive any such conflict that would otherwise kill them. It does so in the way that alters reality the least to accomplish this. For example, if a creature is out to kill the bearer of this curse and there is no reasonable way that they might be convinced otherwise, than the victim may suddenly find themselves in possession of the means to win. Alternatively, if such a creature can be convinced otherwise, the victim of the curse might suddenly know exactly what to say to change the mind of the foe. Otherwise, the foe may suddenly decide of their own accord to spare the victim even while they're winning, depending on the circumstances.
It's worth noting that while the curse seems to take into account any allies its bearer might have when deciding the conflicts that they must face, it doesn't extend any such protections from death to them, meaning while the victim of the curse may survive a conflict, this doesn't mean they win as any or all of their allies could be killed in the process. Additionally, while there is a lower limit to what a victim of the curse might face, there is no upper bounds on this, which can create situations that are virtually impossible to overcome (Though these are rare and tend to empower the victim to overcome them or give the victim the insight required to prevent the worst from happening).
The curse also prevents its victim from succeeding at ending it, because ending the curse could make it so that future conflict doesn't necessarily happen, which contradicts the curse. The curse also prevents any changes in personality and alignment that make conflict unlikely or impossible, such as the victim becoming a pacifist. Finally, because the curse alters reality in the least complex way possible to continue allowing more conflict, this effect could extend to the victim themselves, changing their personality or alignment, or causing the victim to do anything (Whether accidental or apparently intentional) that might cause future conflict. This is usually unnecessary as the universe is big and complex and often doesn't need that much help for conflict to happen, but it CAN happen this way.
In summary, the victim of this curse is fated to never be killed, and always find conflict. Because the nature of conflict is such that a trivial or easily overcome problem isn't considered conflict, the problems this causes are always built to be harder than what the victim has already overcome; But, the victim also can't be killed by the conflict, and therefore often becomes more powerful temporarily or permanently in order to avoid death. When the victim is permanently more powerful, future conflict must be harder. This created a slow but infinite loop of increasing challenge and power creep.
Curing The Adventuring Curse
The design of the curse is such that it cannot be cured by magic or divine intervention, except by The Spellblade of Fire's Primordial Truth feature. The curse was not designed to be cured by The Spellblade of Fire, but is anyway due to the nature of how the Spellblades form their properties on the spot when first summoned, and the nature of the situation in which The Spellblade of Fire is originally summoned. At the DM's discretion, other specific means to cure this curse might exist, but as no one knows of the curse and it was designed to be actually incurable, finding the right specific cure could be an incredibly arduous task of its own right. In general however, the curse resists being cured, because doing so would contradict its own nature. Since it can alter fate itself, this makes it unlikely that The Spellblade of Fire's Primordial Truth feature would ever be used on Shawn Spellblade, and if it was, the two absolute statements of the curse and the Primordial Truth feature would conflict with each other, creating an Avatar of Death with this stat block: . If defeated by The Spellblade of Fire, the curse could then be cured, overwhelmed by the will of the spellblade's wielder.