Warstrider: Symbionts: Warstrider, Book 4

Dev Cameron helped the rebel Confederation defeat the Hegemony forces at Herakles, but his experience merging with an alien Naga consciousness has changed him irrevocably, and the rebellion rages on. After the passive DalRiss unexpectedly attack the Hegemony, Dev and Katya Alessandro are sent to meet with the aliens to determine if they have a common enemy. Their mission is critical to the success of the Confederation, but the difficulty of understanding truly alien intelligences makes a meaningful alliance unlikely, and doubts about Dev's capabilities loom even as he may be the only one able to make contact.