Done 2 space age runs, first on death world - pentapods were crazy to deal with. Both slow progress from learning it and also death world sped up their evolution. In the end I had a chunk wide wall blueprint and beat them with brute force and mass production. Frequently had 100s of buildings destroyed. It didn't matter, I was building hundreds of turrets too.

The intro to all quiet on the western front sums up the feeling of that run. The losses were heavy, but fresh replacements always came.

My second run was a speedrun attempt to get the achievement, made loads of saves as I went and managed to get it with quite a lot of time to spare. Used sandbox a lot to make blueprints.