"Operation Capture"

You can. If possible, weaken them.

How so??

10. weaken non-upgraded neutral armies by repeatedly defeating them.

Even in non-upgraded troops, there's still a stack of upgraded ones... hence the conclusion... it's forbidden... =))). In the rules, it's written... unless you defeat an upgraded stack, then it's allowed. That is, you attack, defeat an upgraded stack, and retreat. Then you attack and kill the non-upgraded ones. But how do you check whether you destroyed the upgraded ones or just attacked and retreated (and the stack disappears anyway)?
PS - I'm participating too =)) I hope I'll have time =))