The Last Mortal Bond by Brian Staveley

As war fractures an empire, three royal siblings—an embattled ruler, a vengeful commando, and a monk trained to strip away emotion—struggle against an ancient, inhuman adversary determined to remake the world. Amid sieges, treachery, and perilous campaigns from deserts to storm-lashed skies, loyalties splinter and terrible bargains are struck. The conflict builds to a brutal reckoning that forces each to choose between saving countless lives and sacrificing the last of their own humanity.

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