The Witcher 4's cinematic reveal trailer was an indulgent six-minute-long saga in which Ciri, the new protagonist of the series, went on a sidequest. The whole thing had the vibe of the Killing Monsters trailer for The Witcher 3, or that one quest where the villagers have been offering sacrifices to leshen.
It begins with someone getting into a bath, only this time it's not Tub Geralt. It's a young woman being prepared for a ritual while her father narrates about how he watched her grow up. That's intercut with footage of Ciri, a character we watched grow up, though we don't see her face. She's using the igni sign to light a fire—possibly burning some herbs to prepare a potion with. Ciri continues to prepare by sharpening a sword, one that looks like the silver version of Zireael seen in the ending of The Witcher 3 where Ciri follows in Geralt's footsteps.