Its time to take a side … A bloody war ravages the oceans. Already, many on both sides have given their lives. Many more will do so before the final ceasefire. Grace Tempest proves her healing powers, working alongside Mosh Zu and Darcy at Sanctuary. She discovers an ancient book, foretelling a shattering prophesy. One twin must die … Oblivious, her brother Connor takes his place at the heart of the Alliance mission to reclaim The Diablo. He is reunited with a former – forever changed – comrade. As the decisive battle looms, each side races to recruit new allies and one twin embarks on a perilous journey to enlist warriors, who long ago relinquished their swords, to join the ultimate fight.