Extremis

More about the book

An implacable foe with telepathic cohesion in battle, near immortality, and eons-advanced engineering skills threatens to wipe humanity from the galaxy. They've overcome their one weakness - no faster-than-light travel - and have followed humanity through our star gates and beyond. But humans are the masters of adaptation and have a counterpunch of devastating proportions in reserve. Now a hard-bitten and brilliant admiral must face down a renewed alien attack and somehow communicate to the enemy that if he is forced to use his ultimate military option, galactic civilization itself may come to a fiery end.