Oath of War by Olena Nikitin

She set the world ablaze… and paid the ultimate price.

Every prison has a weakness, and Annika must find it before the enemy bends her to his will. But time is a luxury she no longer has, and freedom demands a cost few would dare to pay.
As treacherous alliances shift, everything she knows unravels before her eyes.
The Barrier is broken.
The king is dead.
And war has come to the kingdom… but how do you fight Death itself?
The gripping conclusion to The Cursed Bonds duology, where Annika’s fate—and the destiny of her kingdom—hangs by a thread.
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Oath of War is a slow-burn, second-chance, forced-proximity high fantasy with a complex magic system and Slavic mythology-inspired world-building. It is dark romantasy with fae, mages, and dragon riders, and no choosing required.