Help needed for Mission 8

We've been stuck at mission 8 for hours now and finally ran out of ideas on how to beat this mission. Can you guys share some tips/strategies with me that you used to beat it? General tips about strategies that apply to other missions are also appreciated. I know, this is a rather shallow question and I'd love to provide some more detail on our problem, but we really can't figure out what we're doing wrong. Thank you very much!
Report as:
Offensive Spam Harassment Incorrect Board