https://www.reddit.com/r/Higurashinonakakoroni/comments/wu4sn0/higurashi_20th_anniversary_broadcast_to_air_on/
What if the mysterious Beako(who judging from her Hair Decorations is clearly Lambdadelta) is the Beatrice trained by Virgilla? That would mean Virgilla/Kumasawa-San is Hanyuu, Kinzo is Rika and Beatrice Castiglioni is Beako after receiving a fragment of Hanyuu’s Horn.
Beatrice Castiglioni of course failed to get her powers taken back by Hanyuu(who I assume was suspecting Beatrice of causing the Rokkenjima Massacre) due to Rika munching spices and getting drunk knocking Hanyuu out and thus was only shrunk down into the Kuwadorian Beatrice to her chagrin.
Of course Beatrice was later(under Hanyuu’s supervision) pitted against Rika’s Game Pieces(one of which was a piece using the energy that Hanyuu extracted from Beatrice) with the Rosa-Rika Piece(Higurashi Rei Manga Rika I suspect) getting in contact with Beatrice herself convincing her to use her Hanyuu energy to give her her own Hanyuu which she promptly started abusing.
Kuwadorian Beatrice dies being replaced with Yasu as Beako’s new identity and is convinced by Rosa’s Hanyuu to go back to the earlier gameboards and become Shannon AKA Inori Mikazuki emulating Maria-Hanyuu’s AuAus.
She soon found herself still unable to age and resorted to playing other characters like the one representing Kanon.
Eventually Rika’s habit of getting drunk eventually got in the way of her and Satoko’s game so she contacted Beako and decided to finish the Rudolph Ushiromiya game by bringing everything to the Higurashi Rei Visual Novel Setting.
Rika then promptly made Beako(to Beako’s chagrin) acknowledge her as the mother of Beako’s current self before dumping all her Despair and desire to drink into the Bernkastel piece before pitting it against Lambdadelta’s Red Truth before either heading back to her game with Satoko or before examining the remains of Rokkenjima personally.
Rika upon the creation of Bernkastel died as Kinzo and was reborn as Bernkastel and the Rudolf Hanyuu-piece’s child Battler despite treating the Asumu Rika Piece as her current self’s mother.
After Bernkastel gained sentience and became the Witch of Miracles becoming a Miko of Featherine the Witch of Theatergoing, Drama and Spectating the Witch of Certainty Beatrice beat her mentor Featherine’s piece(which had been losing to Beatrice during Ciconia When They Cry before the Gold Eyes Satoko and Rika Pieces became Witches capable of leaving the Gameboards ending the game) with the Hanyuu piece resulting in Red Eyes Rika & Satoko killing each other constantly.
Bernkastel decided to play one Gameboard and Lambdadelta gave her permission to put her pieces wherever she wanted and she dumped the Classmates of Rika and Satoko into the area and had them figure out the reason for Rika and Satoko’s animosity and quell it instantly winning Bernkastel the Game right on the spot.
Beatrice/Beako furious decided to rush over to the original Rika who cured of Drunkeness(by dumping her Despair into Bernkastel) had become Battler. Wanting to trap Bernkastel the Golden witch promptly turned Battler-Rika into Beatrice-Rika(causing Beako to become Lambdadelta in the process) and forced her to play against herself using the wonderous Rokkenjima setting that Rika has interest in to draw in Bernkastel.