Vanguard

Taj is a Vanguard, an elite soldier tasked with defending Acropolis, the last bastion of his people in the Labyrinth. Thousands of years earlier, his ancestors, along with many others, were banished to the vast tunnel network for crimes that have long been forgotten. Deadly creatures hunt them in the dark, and on the surface above, the descendants of their gaolers, the people of Alexandria, threaten them with war and death.

During the cull to keep the creature population at manageable levels, Taj and his unit discover evidence that fabled monsters thought to be safely confined to old stories and legends may have returned. With enemies both above and below, the people of Acropolis are forced into a confrontation that will make them decide what's more important, revenge, or survival.