Cate Blanchett's character in Thor: Ragnarok, Hela, is tremendously important in the Marvel Cinematic Universe. Not only because she's the first female main villain of a Marvel film — though that is very significant — but also because she's immensely powerful, with the potential to really cause a lot of problems for Thor and the other heroes. In the trailers for the film, she is seen destroying the Thunder God's "indestructible" hammer, Mjölnir, but just what are Hela's powers in Thor: Ragnarok?
In the film, Hela is the Asgardian Goddess of Death, and like many of the characters from the Thor movies, she is based on a comic book character who was inspired by Norse mythology. The comic book version of Hela, who first debuted in 1964, was based on the Norse being Hel. Hel wasn't technically a goddess, but rather a cosmic being who ruled over the realm of the undead that bared her name, Hel, which is where the name "Hell" comes from. Marvel took this idea and expanded it to make her the Goddess of Death, while also turning her into more of a straight up villain than she ever was in the ancient Norse religion. So what exactly can the comic book version of the character do?
Like all Asgardians in Marvel comics, particularly the gods and goddesses, Hela is super strong, fast, and resilient; bordering on immortal. However, as Goddess of Death, she also has some extra strength to tap into that makes her stand out a bit from the rest of the Asgardian pantheon. Loki admits in one of the film's trailers that Hela is stronger than both he and Thor, and since he nearly conquered Earth and Thor is the strongest Marvel hero save for Hulk, that's saying something. But she's more than just super strong and durable, she also has a few other special abilities that put her in a league of her own.
Some Asgardians, like Loki and Frigga, have shown magical abilities, but these abilities have typically been considered mere tricks. Hela, on the other hand, wields far more powerful magic, including the ability to channel magical energy into her hand in a technique she calls her "Hand of Glory." This is likely what is going on in the film when she destroys Thor's hammer simply by holding it in her hand. She is also capable of projecting this energy to devastating effect, and she has the ability to travel through the astral plane, like Doctor Strange, and is just as powerful in her astral form as she is in the real world. In the comics, Hela can even utilize a touch of death to kill someone — including Asgardian deities — simply by placing her hand on them.
Since she's the Goddess of Death, Hela has some control over the dead. This means she can command an army of the souls who reside in her realm, and it appears in the trailers that she does this in the film in order to conquer Asgard. Another ability of hers that seems to pop up somewhat frequently in the movie is the way she manifests her magical sword, Nightsword, out of thin air. Nightsword is a highly indestructible weapon, and Hela is of course very adept at using it.
Hela is not just the first female villain in a Marvel movie; her combination of tremendous strength and magical powers also make her one of the most formidable foes to ever show up in the MCU. No wonder Thor has to enlist the help of Thor, Loki, and Valkyrie to try and stop her — the Goddess of Death is not messing around.