CD Projekt RED recently announced, The Witcher 4 is a brand new adventure in the popular RPG series. It captures former protagonist Geralt of Rivia as he retires from life as a warlock while his adopted daughter Ciri takes up the mantle. While The Witcher 4 will probably focus on telling a new story and introducing new characters, it may also be a great opportunity to introduce one character from Andrzej Sapkowski's original novels: Francesca Findabair, a powerful witch and one of the leaders of the elves.

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Maybe secondary heroes for The Witcher 4
With Ciri confirmed as the main protagonist for The Witcher 4, there are still some characters who could make exciting secondary protagonists.
Who is Francesca Findabair?
Francesca Findabair, also known as Enid an Gleanna (Daisy of the Valleys) was the leader of Dol Blathanna, one of the few remaining elven settlements. She was also a powerful sorceress and a member of the Sorcerer's Brotherhood. However, she and her Scoia'tel forces secretly worked with Emperor Emhyr var Emreis of Nilfgaard to betray the Brotherood in exchange for allowing Dol Blathanna to exist as an independent state.
Somewhat regretting her betrayal, Francesca safely smuggles Yennefer of Vengerberg away from the fight and later joins Yennefer, Triss Merigold, Phillippa Eilhart, and several surviving witches to form the Witch Lodge. The Lodge tries to recruit Ciri but ultimately fails and later disbands. Francesca does not appear in any of them Charmer video games, although it is stated that he is still alive and leading the elves va journal entry The Witcher 2: Assassin of Kings and serves as the leader of the Gwent faction Scoia'tel v The Witcher 3: Wild Hunt
She Has A Vested Interest In Ciri Because Of Her Elder Blood
From wild hunt Francesca is the only member of the Lodge of Witches who has never physically appeared in va Charmer video game, though he plays a role in seasons 2 and 3 of the Netflix series. While that alone is enough to warrant her appearance in the fourth game, her status as a powerful elven leader and sorceress makes her a particularly fitting character for Ciri's story.
She is an elder blood expert who could help or stop Ciri
The Elves have always had a special interest in Ciri, as she is a descendant of the powerful Lara Dorren and has Elder blood of her own. This grants her unusual abilities that manifest as teleportation, time and dimensional travel, the ability to stun enemies with screams, and more. While novels and Wild Hunt centering on the Aen Elle, otherworldly elves led by the villainous Eredin, and their pursuit of Ciri, it's certainly possible that Francesca and the elves of Dol Blathanna could also be interested in the young warlock.
While Francesca does not have as much knowledge of the Elder Blood as her fellow elven sorceress Ida Emean aep Siveny, who appears briefly in Wild Hunt advise Yennefer, she has some ability to identify it. One of her cards Gwent: The Witcher Card Game he mentions a time in Francesca's past when she was able to tell if the children had elder blood or not. Her knowledge and power could make her a valuable ally or mentor for Ciri.
Alternatively, Daisy of the Valleys could serve as an antagonist much like Eredin before her. In the books and especially in the Netflix series, Francesca has shown herself to be willing to make tough decisions, putting the well-being of her people and the safety of Dol Blathanna above all else. If she felt that gaining access to Cira's blood and powers could help the elves, she would stop at nothing to achieve that goal. Whether as friend or foe, The Witcher 4 would be the perfect time for this long-awaited character to finally appear.

The Witcher IV