WARNING: The following contains major spoilers for Darkhold: Omega #1, available now from Marvel.
The dark elder god Chthon has arisen once more to threaten the Marvel Universe. In a bid to stave off his emergence on Earth, some of its greatest heroes have turned to the pages of the Darkhold. These nightmarish Avengers are as powerful as ever, but still not enough to defeat Chthon. Thankfully, the Scarlet Witch has had her own plan brewing all along. Not only has she just put an end to Chthon's invasion, she has turned his most wicked creation into the latest addition to her own list of terrifying powers.
The Darkhold Avengers have escaped their personal nightmares and arrived back in the real world to do battle with Chthon. With their newfound unholy strength, these heroes have no problem tearing their way through Chthon's hordes. Once the elder god himself arrives on the battlefield, however, not even their combined might stands a chance against him. The Scarlet Witch and Doctor Doom arrive with the true Darkhold in hand to put a stop to the fight, though not in the way they had originally intended. When Doom stands poised to unleash the powers of the ancient tome upon its maker, he is betrayed by Wanda who takes the book for herself. Scarlet Witch doesn't just turn the Darkhold's power to turn the tide of battle, though, she rewrites it in her own image.
After being tormented, tortured, and possessed by Chthon over the course of decades, Wanda takes the ultimate revenge by quite literally becoming the true Darkhold. With her powers Wanda consumes the book, binding it and everything it contains to her own soul. With this astounding act she locks Chthon away once again. She also now holds dominion over the Darkhold's powers. As such, it takes little more than a thought for her to return the Darkhold Avengers to their proper forms, leaving them with only glimpses of their experiences within its pages.
Being able to set things right for her allies and save the world from a demonic takeover in one day is certainly one of the most impressive feats that Wanda Maximoff has accomplished in her career. Unfortunately, it is also one of the more unsettling ways this saga could have ended. The Scarlet Witch has always been one of the least stable characters in the entire Marvel Universe. That coupled with her reality warping powers, ones which have subconsciously altered the world around her several times, also make her one of the most potentially dangerous magic users. Wanda has come to terms with her past, with some of the biggest strides towards that coming alongside the shocking events of her own death and resurrection in recent months. Still, being in a better place doesn't mean she isn't still someone to fear, especially with new eldritch magic at her fingertips.
There is also the fact that Wanda is now tied directly to Chthon and the Darkhold. Both would be unleashed upon the world with her hypothetical demise. She may be relatively immortal, but that hinges on her effectively willing herself back to life. Even if no one tries to take advantage of that fact and unleash another demonic invasion on Earth by trying to kill her, Wanda has effectively started a doomsday clock on just such an eventuality. With any luck, she has plans in store for that outcome. If not, then the only question left is when the Marvel Universe will see the horrors of the Darkhold next.