Well, after a little bit of research, I have been able to determine that only the attack power (with ally bonus included) matters when it comes to quests. Since others had written on this forum that it was atk+def, I thought that I would let everybody know I wish I had known... I built 24 aviaries because they had higher atk+def, and now it turns out that I'd have been better off with 24 factories. Oh, well, aviaries will be better in the long run. Since I'm already writing, let me also share that..... I am down to the last quest... yeah!! :mrgreen:
I think also spy stats have some effect. See me for example, spy build. Yet I can complete last quest no problem. My bfa sucks and my bfe isn't that good neither.