Ironbound
Andrew Givler
In the Iron Empire, only the strongest are given a chance to Ascend. Castor has always wanted to fuse with a Cor Heart and bind a Symbol to manipulate the elements, but when his trial day is shattered by attack, he is conscripted into the Legions bound to a Symbol he never wanted. He must survive the Iron City, the frozen North, and traitors within the rusting Empire — driven above all by revenge for his family. (Publisher blurb via Goodreads.)
Progression: Ascension-gated power ladder in the Iron Empire. Worthy youths compete in a trial (the Sententia) to win the Empress's blessing and fuse with a Cor Heart made of otherworldly metal, which grants the ability to bind a Symbol and manipulate the elements. Advancement continues through Iron Legion service and the great Houses, with further Ascents marked by binding additional Symbols (book 2: a secret second Symbol) and reaching new heights of Cor Heart power. Publisher markets it explicitly as a 'Progression Fantasy Epic'; Goodreads shelves include litrpg.
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