The last book in the story. I never thought out the rest and in fact this idea can be squished into two books if done right. However book three would go something like this.
They make it to Italy and are now trapped most of the book is a power play baiscly like those horror movies where the Main characters are stuck together and things happen. Aro and marcus are there Marcus making a remake about the relationships in the room and wanting to see them tested. They Leave them to Jane and Alec first a fight ensues while they watch from another room. With some of the main party injured and Alec dead jane is told to go back despite wanting to kill them all. Aro sees her as a danger but lets her live knocking her out and telling them to lock her up. They then Call in Chelsea who messes with everyones connection and emotional bond making Jacob fall in love with Bella, Making Edward fall in Love with bella, Leah is hurt, And she tests Alices love for Jasper. The last piece of the puzzle to Jasper and alices background is reviled
How it was Jasper who freed alice but due to Chelsea fell into a depression before being sent to back home to texas to fight the war. Meanwhile alice finally found her (adopted) family finding out that members were dead and visiting their graves.
The last member they send in to fight the now askew team is Renata who has the shild like ablity. Everyone is off their game and really book three is a big character growth, character study, with fighting.
The end of the book would end with Bella, now a strong huntress keeping in touch with training with jacob, some of the Voltaire and some cullens dead now, and an open ending for “possible” sequels and fanfiction/ fan interpretation