Fans were understandably displeased when Scarlet Witch was introduced in Avengers: Age of Ultron. The terrifyingly powerful sorceress who could rewrite entire realities in the comics was reduced to some glowy red telekinesis and the ability to project visions into people's minds. There's a moment she's even afraid to step out onto the battlefield, showing how fearful and uncertain of her powers she is. The Wanda Maximoff in Avengers: Age of Ultron wasn't the same hero, who has, at times, been one of the most dangerous entities in the comics.

Related: Dead MCU Characters Who Can Return In WandaVision

To some extent, the fluctuating powers in the MCU are understandable. It's the same as any role-playing game: Magic s may start out squishy, but at higher levels, they're near-unbeatable characters with broken power sets. Had the MCU allowed Scarlet Witch to command her full comic book powers right away, she would have wiped the floor with everyone else. No matter how impressive Avengers like Iron Man and Captain America are, there's no beating a chaos witch who can warp the fabric of reality.

But Scarlet Witch has been one of the rare characters, magic-s or otherwise, whose powers have leveled up considerably as the MCU has progressed. The girl who could initially only cause single-person projections and rip apart a few robots in Age of Ultron is now (likely) creating entire realities in WandaVision. How did she get from Point A to Point B? It's likely the Mind Stone is the reason Scarlet Witch has become such a powerful sorceress.

Wanda's Own Powers Come From The Mind Stone

In the new trailer for WandaVision, the Mind Stone featured prominently toward the end. The yellow Infinity Stone is shown floating in front of Wanda before breaking apart. It's a callback to the events of Infinity War, in which a heartbroken Wanda has to use her powers to destroy the Mind Stone in Vision's forehead in order to keep Thanos from getting it. While she succeeds and the Mind Stone shatters, Thanos then reverts time in order to take the Mind Stone, this time crushing Vision's head and killing him for real in the process. At the time, audiences focused on the heartbreak of Wanda losing Vision and then being dusted herself.

However, even though Thanos rewound time by a minute, the other timeline – the one in which Wanda destroyed the stone herself – still exists. Everyone associates the Mind Stone with Vision with good reason. But Wanda herself has stronger ties to it beyond it being the stone in her partner's forehead. Earlier in the movie, Vision explains Wanda is the only one who can destroy the Mind Stone because her energy signature matches it, as she herself got her powers from that same stone. What's more, it's been helping her become more powerful since the events of Infinity War. Consider all that's happened since.

Related: Avengers: Why Vision Is Less Powerful After Age of Ultron

Scarlet Witch Is Suddenly More Powerful In Endgame

At the end of Avengers: Infinity War, Wanda is dusted alongside half the other Avengers. For five years, the dusted characters, including Scarlet Witch, simply ceased to exist. This much was explained when Peter Parker popped back through a portal and started excitedly babbling to Tony Stark about how they were on another planet and then suddenly they were on Earth again.

But when Scarlet Witch returns in Avengers: Endgame from a state of nonexistence, she's suddenly more powerful. In fact, she almost singlehandedly destroys Thanos. It's something that could be explained by her fury and rage making her temporarily more powerful, but that's a much larger jump in abilities than what can be justified by emotion. It appears as though somehow, Wanda managed to level up in her powers in the last five years in an enormous way. The only thing that could have done that is something that exists outside of time and space: the Mind Stone. It's the last thing Wanda interacted with before being dusted. If their energies fused, then the Mind Stone quite literally may have become a part of her, or at least transferred some of its power to her.

The Mind Stone Helps Scarlet Witch Create WandaVision's Alternate Reality

This last bit is born out by the WandaVision trailer. In it, Wanda doesn't look at the shot of the Mind Stone shattering with grief, as she does in Infinity War, but with something closer to awestruck wonder. It's clearly revealing something wonderful to her. The stone could be showing Scarlet Witch new possibilities or unlocking her vast potential. She could even be recreating it from her own self after absorbing its energies in Infinity War.

This is important for the events of WandaVision, as it indicates Wanda has leveled up in her powers even more than what was shown in Avengers: Endgame. Almost tearing apart an ultrapowerful being is impressive enough, but if WandaVision is indeed following the "House of M" story from the comics, as appears to be the case, then Scarlet Witch has evolved again in her powers. Creating an entirely new reality so powerful and real it sucks other characters into it is far beyond what Wanda was capable of before. Finally, the MCU is getting to the insanely powerful sorceress of the comics, the one who can rewrite entire timelines and change entire realities. It just took the Mind Stone and Vision's death to do it.

Related: WandaVision Trailer Teases The MCU's House of M

The Mind Stone Takes The Place Of Charles Xavier In The Comics

In the "House of M" storyline in the comics, a heartbroken Wanda has a mental breakdown after the loss of her children with Vision. Her grief and unstable mental state start warping reality to a dangerous degree, so Magneto and Charles Xavier spirit her away to the island of Genosha in an attempt to get her under control. Professor X attempts to use his own psychic powers to heal her, but even his enormously powerful skills aren't enough to heal her fractured mind. All he can do is try to guide her to channel her powers into safer waters, but it soon becomes clear Wanda is too much of a threat to the world (if not universe) to be allowed to live. Scarlet Witch's twin brother, Quicksilver, gets word of the plan and warns Wanda ahead of time. However, thanks to Professor X's influence and his injection of psychic powers putting her mind somewhat back together, Wanda is now powerful enough to create an alternate reality known as House of M.

This new reality is so real and all-encoming it replaced actual reality for a short while in the Marvel Comics. What's more, it wasn't just Wanda living in her own little escapist bubble, but all the Marvel superheroes living in this new reality where their hearts' desires have been granted. That's a level of power beyond anything Scarlet Witch had ever exhibited before, and it appears to be the same in WandaVision. The first WandaVision trailer shows Monica Rambeau being pulled through multiple realities. The second finds her showing up on Wanda's doorstep but unable to who she is or how she got there. It's the same with Kathryn Hahn's character in the first trailer. She knows she's no longer in her normal reality but isn't sure what's happened.

To pull all that off without even realizing one is doing it takes an enormously powerful mind. Though Wanda was formidable before, it's a level of raw chaos magic and a mental capacity that requires a boost from somewhere or something. That something is the Mind Stone, which, within the context of the MCU, acts in the place of Professor X as the catalyst that juices up Scarlet Witch's magic enough for her to create what we see in WandaVision. The Mind Stone merging with Wanda in Infinity War, or at least unlocking her vast potential, is the only thing that explains how she's grown so much more powerful over the last few movies. It will be quite a bit of fun to see just how powerful she is when WandaVision hits Disney+ in January.

Next: WandaVision Can Fix A Scarlet Witch & Vision Infinity War Problem