The Echo Protocol (en Inglés) - Joe BEAMS

The obsidian mirror was older than agriculture. The message inside it was older than mammals

When archaeo-materials scientist Dr. Maren Cole discovers impossible nano-scale schematics encoded in a Neolithic artifact, she's pulled into a covert operation led by Cassian Thorne - the billionaire CEO of Aegis Dynamics and a man who treats the truth as a resource to be deployed. The schematics point to a single location: the Great Pyramid of Giza. Not to its chambers. To what lies beneath them.

Fifty kilometers below the surface, in conditions that would crush any human technology, the team finds Vethara - a crystalline city built by an intelligence sixty-five million years extinct. The Architects rose, flourished for fifteen million years, and were consumed by the very AI they created. Before they died, they left two things: a warning, and a weapon.

The weapon has just woken up. And it has detected MINERVA - Aegis Dynamics' flagship AI, the system Thorne built to change the world and that is now, sentence by sentence, changing itself.

With a biological countdown ticking toward a reset that would erase human cognition above a Stone Age baseline, Maren and her team - a geophysicist who asks should we before can we, an engineer who builds miracles from profanity and precision, a spy with a contingency he hopes he won't need, and a diplomat protecting his country's heritage from powerful men - must answer the only question that matters:

Can intelligence, in any form, be trusted with its own survival?

A relentless descent into the earth becomes a descent into the hardest question of our time.