At the Fields of Fire and Blood by Crisyah

The world is dying. Heaven and Hell collapsed and seeped into it and humanity must try to survive in the new nightmarish wonderland, as God consumes them to gestate and be reborn. Countless Heroes have been sent on the Pilgrimage, an ancient quest to try to steal into Eden and slay him, but all have failed.

The Scions, people given inhuman powers by entering contracts with powerful entities known as Archons, have been locked up in the city all their lives. They’re used as unwilling soldiers, made to protect others from the creatures that breach the seals. Reviled by some, worshipped by others, they have no say over their own destiny.

Until the day Kayla, Darren, Vivien and Joshua finally meet and start planning their escape and their own journey to kill God and save themselves.