Update - March 22: It turns out that the first teaser image for The Witcher 4 – or whatever its official title ends up being, since we know it's not technically called The Witcher 4 even though there's nothing else to call it – depicts a medallion from the School of the Lynx, which pretty thoroughly shuts down the School of the Cat theories sparked by first impressions.
Global community director Marcin Momot of developer CD Projekt Red confirmed on Twitter (opens in new tab) that the medallion belongs to the School of the Lynx. There was never any doubt that the medal wasn't from the School of the Wolf, and its half-buried catlike features were just vague enough to implicate the School of the Cat and Ciri with it, but this medallion actually belongs to the Witchers of a very specific feline faction.
The School of the Lynx has a more tenuous presence in the Witcher universe on account of it being largely rooted in footnotes and fan-fiction. The fact that it's seemingly at the heart of the "new saga" that the next Witcher game is planning implies that Geralt has indeed left center stage, but with the School of the Cat largely out of the theorycrafting picture, there's now less to suggest that Ciri will take his place as the lead in the story, and less still about what her challenges and motivations might be. So we're not quite back to square one, but we're pretty close to it, and we likely won't get more story details for some time.
Original story: The first teaser image for The Witcher 4 suggests that its main character could be Ciri, the adopted daughter of series protagonist Geralt.
As developer CD Projekt Red noted in a brief announcement confirming that The Witcher 4 is officially in development, the reveal image features a Witcher medallion and promises "a new saga" for the franchise. It's clear that big changes are coming to the Witcher games, and that medallion could be a big clue.
It's partially buried in snow, but the featured medallion seems to belong to the School of the Cat, which oversees a separate Witcher faction than the School of the Wolf that Geralt follows. Ciri initially trained under Geralt at Kaer Morhen, the base of the School of the Wolf, but she did come to possess a medallion of the Cat after seizing it from Leo Bonhart, who was said to have killed at least three Witchers.
This isn't just coming from the Witcher books, either. Ciri is shown sporting a medallion of the Cat in The Witcher 3, so if this teaser image is as literal as it seems, The Witcher 4, or whatever its final title ends up being, could well be a new story starring Ciri that picks up after the events of The Witcher 3 and its canon ending.
We're veering even further into speculation here, but on top of hitting some popular story beats, casting Ciri as the playable character of the next Witcher game could also allow CD Projekt Red to go wild with gameplay. Ciri possesses Elder blood, after all, and has access to rare and powerful magics which would probably be pretty fun to wield in combat and use in exploration.
It's still unclear what's in store for The Witcher 4, including its official title and release date, but we can safely assume that its "new saga" will take the series to unfamiliar territory. Whether Ciri plays a central part in that remains to be seen, but fans of the Cintran princess have never been more favored.
We do have one bit of concrete information: there are no plans for The Witcher 4 to be an Epic Store exclusive on PC.