Screen Rant

A sizzle reel for Star Wars: The Rise of Skywalker shows Rey wielding a red, double-bladed lightsaber! 1 / 8

The scene doesn't come with any context, but Rey wielding a weapon of the Sith is worrying. 2 / 8

Rey was tempted by the dark side of the Force in The Last Jedi, so it's possible she may have succumbed. 3 / 8

And while that isn't impossible, it's more likely that Rey must take up an enemy's weapon in order to fight. 4 / 8

So whose weapon is it? One possibility is it belongs to one of the newly unveiled Sith Troopers. 5 / 8

The Sith Troopers are loyal to Kylo and he may have outfitted them with traditional Sith weapons. 6 / 8

In which case, a red, double-bladed lightsaber would fit in perfectly. 7 / 8

The Rise of Skywalker sizzle reel is expected to be released soon, and then we may learn why Rey wields a red lightsaber. 8 / 8