RoboTech: The Sentinels #5: Rubicon

Optera! Birthplace of the Flowers of Life and their agents of retribution, the Invid . . . nexus for an unfolding of events that had left the galaxy reshaped and redefined . . . and now the focal point of the Sentinels' long campaign to liberate the Quadrant from the Regent's tyranny.
Edwards is on his way to Optera, in flight from Tirol with his prisoner Lynn-Minmei and a handful of Invid Inorganics under his control. So too are Breetai's Zentraedi — closing on the very world the Imperative bade them defoliate generations ago — and the renegade forces of Tesla, mutated beyond recognition by the fruits of the Flower.
The Sentinels themselves are not far behind. However, they have Peryton to deal with first — a godforsaken planet cursed by fate and time itself. But what awaits Rick, Lisa, and the Human Sentinels there is a mere primer for what is to come: the realization that they have journeyed across the galaxy . . . to wage war against each other!