Taigawa wrote:How does one defend against an exterminatus?
There are a variety of ways a species can defend against itself being exterminated. And I encourage you to play around with ideas, you may as well figure out something none of us have previously. A few of these I have used myself in past RP ideas.
The first and the most obvious, is to flee. Part of my backstory canon involves just that. Where I fled my 'home' galaxy to escape a loosing struggle against a sorta Halo Flood/40k Tyrannid combo. A single ship which was the culmination of my civilizations remaining resources made it to the MWG to start a new.
The second way is deception. In another RP I faced a not only numerically superior force, but a technological superior force as well. They had appeared in one of my fringe colonial systems and after a misunderstanding proceeded to lay waste to the system. Faced with another dilemma, I came up with another solution. Instead of running away with my tail between my legs again, but also realizing a stand up head to head confrontation was not going to end in my favor. I decided to deceive the invading forces. I made it seem like one of my other frontier worlds was my 'capital/home system' by re routing extra traffic, inflating signal frequencies, and my editing star maps and trade lanes. When they eventually destroyed that system, they believed their work to be done and promptly faded back into the depths of the Gamma Quadrant, leaving me to survive once again.
Of course you can always struggle militarily against the invading exterminating threat. Just remember you have to make the cost of continuing their extermination greater than their capacity to continue. Only then will they eventually break contact and give up.
I hope some of this helps!