[Von Himmel]

^

Spoiler:

..I don't think they're actually getting 'serious' at all. In the first place, I don't even think that they understand such basic concept of emotion; they just learned much about human strategy because of Sumika and that's why they can use tactics to attack the humans.

Start puting all that effort they put into TSF development into making super tanks instead...

I don't tank is a good choice for hive infiltration.