Exalted of the Wyld: The Arcadians
(I use the term Arcadian here to refer collectively to all Wyld Exalt types. Credit for that name goes to its original creator.)
(In designing these Arcadians, I used Second Edition's Exalted Core Book and Wyld Compass Book, but First Edition's Fair Folk Exalted Power Book.)
The Arcadian Exalts are neither cured of, nor suffer from, the Great Curse. Rather, they embrace and make use of the curse, bending it to the plot, guiding it with the narrative of their place in the Wyld's ever-changing story. (For details about the mechanics of this change, as well as rules for Exalt types that do not suffer from the Great Curse, see Chakras: Changing Sides.)
The Primordials are, ultimately, creatures of the Wyld, born of it and defined by it. They despise chaos not because it is unknown, but because they know it only too well, and nothing is stopping them from making use of it aside from their own utter distaste for it. It would seem only natural, then, when wishing the worst one can think of upon one's enemy, to curse them with that which one despises the most. Thus the Neverborn cursed the Exalted with Chaos, a slow and steady dissolution to the madness from which everything was born. So long as she remains in ignorance/denial, believing in and insisting on her own sanity and purity, her Shard will remain tainted but whole; a fully Limit-Broken Solar will still, despite her madness, have a Solar castemark and anima and charms. But if, in the moment of Limit Break, an Exalt chooses voluntarily to embrace that state, to accept the madness and the chaos with which she has been cursed, her Shard is overtaken and permanently twisted by that ultimate curse of chaos, utterly reshaped by it from that moment until reincarnation.
These willful harbingers of madness are the Arcadians, Exalted of the Wyld.
When the Neverborn laid the Great Curse upon their enemies, it was designed to be resisted. It was strong, enduring, laced with dormant energies to firmly but steadily push its influence on its host. For all their hatred of the Exalted, for all their disdain and enmity, they never doubted that they shared a common enemy in the Chaos of the Wyld. It never occurred to them that the curse might be embraced.
When an Exalt opens up and voluntarily accepts the Curse of Madness resident in her Shard, that slow seeping battery goes off like a capacitor. The resulting release of power warps and twists the Shard like a concussive cancer, forming a Grace like a tumor in the very crux of its essence. Unlike the Graces of the Fair Folk, this new malignant Grace is not out in the open and vulnerable; it cannot be attacked or broken, at least, not easily. It is not an outer piece of her being, rather it has taken hold in the very crux of her Exaltation, surrounded and protected by the very Shard it corrupts. The burst of energy also channels 100*Essence EXP into the new Arcadian, spendable on anything, purchasable immediately, allowing her instant exploration into the powers and abilities her new Grace makes available to her. (Note that this requires a minimum of one Permanent Plot; you have be at least a little crazy if you want to dive headfirst into full-on madness.)
Mechanically, the character no longer has Limit; instead she has Lure and Bedlam (Exalted: The Fair Folk, p.112). She gains access to the shaping actions and Fair Folk charms of her newly formed Grace (which matches her highest Virtue), but also still has access to her Exaltation's charms. She can no longer respire Creation's Essence naturally, but she can attune to and use Hearthstones aspected to her Exaltation. She can respire Wyld Essence and feed on Virtues like the Raksha do (her one Grace is a feeding maw), but she cannot possess Pennants or Cysts or otherwise attune to Freeholds (trade-off for retaining the ability to use Hearthstones and attune to Manses). Caste marks and Anima flares will still happen (though their look is much changed by their new Arcadian caste), however the Anima loses the beneficial effects it once had, now serving only to give away her nature as an Arcadian Anathema.
The one thing about Arcadian Exalts that makes them terrifying, both to their enemies and to those considering playing them, is that they are by definition beyond redemption. The Raksha do not have a supply of Arcadian Shards to dole out, as the Neverborn and Yozi do; nobody initially Exalts as an Arcadian. A Shard can only change templates once in an Exalt's lifetime, and an Arcadian Shard has by definition already done so. Arcadians are powerful and versatile, to be sure, but beware taking on the mantle of the mad.
For rest assured, when you embrace Chaos, there is no going back.