Now, humans are bent on destroying the aliens before they destroy human-kind, and the Kir struggle to hold onto their ancient home worlds that had stood for nearly 3 millenium, and the colonies that were started hundreds of years before human kind ventured into the quadrant.

The Kir use Grav technology very efficiently. That and the use of AI, or Artificial Intelligence. Self analyzing computer warriors that are sent in ahead of an assault force to draw the enemy away from the intended landing zone. They are also very effective Shock Troops, as they have no moral or fear.