Eternal Guardians. Apocalypse Adventures Chronicles, #5

When his city faces annihilation, street-smart Valen must choose between hiding... or becoming something beyond human. Valen Thornwick never wanted to be a hero. As a former thief turned reluctant city defender, all he cared about was keeping the people of Haarwatch alive when cosmic horrors started tearing reality apart. But when an ancient evil breaks free from its prison, normal weapons and tactics become useless.
The only way to stop it requires the Guardian Protocol-a magical transformation that grants incredible power at a terrible cost. The price? Your humanity. Now Valen and his team must master reality-bending abilities, form unbreakable bonds with each other, and face enemies that can rewrite the laws of physics with a thought. Each level gained brings new powers but pushes them further from the people they used to be.
With his corruption levels rising and time running out, Valen discovers the truth: saving his world means choosing between staying human... or transcending into something that can protect everyone he loves forever.