Two approaches to solving the problem.
One is to try and solve it through purely technological means.
No matter how powerful the microbes are, they are still microbes. Even though they inevitably contain certain Extraordinary Powers, technology developed based on the truths of matter is equally formidable.
Moreover, the Interstellar Civilization now possesses extensive research experience in the Extraordinary Domain and is no longer as weak in terms of Extraordinary concepts as it was at the start. Research technologies in related domains are already quite advanced.
Many past crises in the microbial domain have been resolved in this way.
However, the time required for this process is considerable.
The second approach is to consider solving it through the Extraordinary Domain.
The Immortal Cultivation Civilization and the Magic Civilization can both find ways to potentially deal with these microbial monsters at scale based on their respective approaches.
