Rey's Sith dagger could be the key to Star Wars: The Rise of Skywalker. Lucasfilm has become renowned for the "Mystery Box" approach to marketing that writer/director J.J. Abrams considers his stock in trade. Star Wars trailers conceal rather than reveal, dropping subtle hints and avoiding outlining the story beats. With Abrams himself returning for Star Wars: The Rise of Skywalker, it's no surprise that the trailers for the film have been less than illuminating.

The biggest news, of course, is that Emperor Palpatine is returning. Although the Sith Lord was killed by his apprentice in Return of the Jedi, Darth Sidious is back, having proved himself powerful enough to conquer death itself. The final Star Wars: The Rise of Skywalker trailer confirmed that he's back in his physical form, and it featured dialogue in which the Emperor claimed the "coming together" of disparate forces played right into his hands. Most viewers assume he was actually talking about Rey and Kylo Ren, adversaries who have a strange, powerful connection in the Force.

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Naturally, there's intense speculation about just how the Emperor has returned - and how has he will be defeated. One subtle detail in the latest Star Wars: The Rise of Skywalker trailer may have hinted at a possible solution to the galaxy's Emperor problem.

Rey’s Sith Dagger In The Rise Of Skywalker

Rey and Kylo Ren Vader's Mask Star Wars 9

One mysterious shot in the trailer shows Rey and Kylo Ren working together to shatter something with their lightsabers. They appear to be destroying Darth Vader's mask for some reason, and the way it explodes suggests that it has been enchanted with Sith sorcery. The whole scene is very confusing, but look closely and one particular detail stands out; while Rey is holding her lightsaber in one hand, in the other she's holding a dagger. The handle's design is similar to a Shikkar, a Sith dagger from the old Expanded Universe. Although some Sith used Shikkars for decoration, they were traditionally assassination tools. The classic Shikkar has a glass blade that's particularly fragile around the hilt, meaning an assassin would stab someone with the knife and then twist the handle to break the blade off, leaving it embedded inside the body.

There have long been rumors that a Sith dagger would play a prominent role in Star Wars: The Rise of Skywalker, with reports that the Resistance would discover the ancient weapon. According to these unconfirmed reports, the Resistance would need to reprogram C-3PO in order to translate the Sith runes inscribed on its handle, with protocol droids programmed so as not to be able to translate ancient Sith. That would fit with the trailer, which shows droidsmith Babu Frik attempting to hack into Threepio's core processor.

Is Rey’s Knife The Dagger Of Mortis?

It's important to note that, while Rey's dagger is similar to a Shikkar, it doesn't look quite the same. Another possibility is that this is the mystical Dagger of Mortis, an ancient and mysterious blade introduced by George Lucas himself in the Clone Wars animated series. One of Lucas' favorite stories explored the theme of the Chosen One, with Anakin Skywalker, Obi-Wan Kenobi, and Ahsoka Tano transported to the world of Mortis, where they dealt with what appeared to be physical representations of the light and dark sides of the Force. The Dagger of Mortis was the one weapon that could kill these enigmatic, archetypal beings.

When Disney purchased Lucasfilm in 2012, they decided to declare the old Expanded Universe non-canon, or "Legends". They've since happily mined the EU for its best concepts and ideas, most notably characters like Grand Admiral Thrawn. Given that's the case, it's perhaps significant that the EU expanded upon the Dagger of Mortis, revealing it was enchanted and able to kill even immortal beings. Luke Skywalker quested to acquire the Dagger of Mortis as insurance against another of these archetypes, who were referred to as The Ones.

Related: Everything We Know About Darth Vader's Presence In Star Wars 9

Rey’s Dagger Could Be Used To Kill Palpatine

Palpatine Force Ghost in Star Wars The Rise of Skywalker

If Rey's dagger is indeed the Dagger of Mortis, then it could clearly play a crucial role in Star Wars: The Rise of Skywalker, given she appears to be taking on a dark side being who has conquered death. It's long been clear that Palpatine came closer than most Sith to discovering the secret of eternal life. In Star Wars: Episode III - Revenge of the Sith, Darth Sidious attempted to seduce Anakin Skywalker with the lure of the dark side, and he tempted him with the tale of Darth Plagueis the Wise, a Sith who had learned how to conquer death.

The future Emperor was careful not to explain what this means, let alone how it could be achieved through the dark side, but he seemed to believe it. Interestingly, Matt Stover's novelization went a step further, with Palpatine suggesting that Plagueis' apprentice - i.e. himself - may well be "virtually immortal." The novelization's canonicity is disputed, but the fact remains that Stover worked closely with George Lucas himself, and had Lucas' approval for the edits he made. Many of them were inspired by earlier drafts, so likely accurately reflect Lucas' own thinking.

Notice the clear parallels, then; Rey is confronting a being who is functionally immortal, and the Star Wars: The Rise of Skywalker trailer shows her wielding a weapon that has the ability to kill even immortal beings. This could be the only thing that can kill Palpatine himself.

Rey’s Dagger Could Be Used To Bring Balance To The Force

The Mortis arc in Clone Wars was focused on the theme of balance, and the Dagger of Mortis was designed to prevent the Force going out of balance. It was owned by Father, who served a sort of "Chosen One" role and could use it to kill the archetypal beings who represented the light and dark sides of the Force should either become too dominant. Interestingly, the Disney era of Star Wars has increasingly treated balance in this kind of way, as a separate concept to the light and dark. The Jedi themselves only pay lip-service to this, vaguely believing that "balance" means the light should be dominant, which explains why they misunderstood the Chosen One prophecy. In reality, a galaxy in balance features both light and darkness, a sort of cosmic yin-and-yang.

But Palpatine is a living imbalance in the Force, the dark side ascendant. Having learned the secret of immortality, he's essentially become the archetype of the dark side, and he's been planning his return from the shadows for quite some time. "Long have I waited," the Emperor hisses in Star Wars: The Rise of Skywalker's final trailer. That means the Dagger of Mortis would be fulfilling its purpose if it was used to slay Palpatine, which would explain why its inscriptions guide Rey to the Emperor, its mystically assigned target. Furthermore, while Rey is shown holding in the trailer, the final deed may not be done by her at all. The prophecy of the Chosen One says that "a Chosen One shall come, born of no father, and through him will ultimate balance in the Force be restored." That could quite easily be fulfilled through Anakin Skywalker's lineage, as Kylo Ren uses the Dagger of Mortis to kill the immortal being Darth Sidious has become.

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