Proof of Concept

The Undead have been blooded in combat. Now it's time to prove their value.
The huge cost and effort to reanimate them must be worth it. With no rights of their own, their very existence depends upon their return on investment.
But as the Undead are finding their footing and discovering how to best fight the war with the Tucanan invaders, the aliens are not standing still. They are experimenting with their evolutionary past to create new ways to fight humanity's military forces.
It's become an arms race. Which species can stay ahead of the other? Which one can gain the advantage?
For every new innovation, there is a counter, and when the Undead's secret base on Opal-3 is attacked by the Tucanans, is that just a coincidence? Or is it an effort to wipe out the Undead Marines before they can establish themselves?
With pressure from the bean counters to prove their value on one side and the Tucanans' invasion on the other, the Marines could be snuffed out before they ever really establish themselves as the premier fighting force of humanity.