Defending allied cities

I think something like this should be an optional Strat

Been suggested before, good idea, previous devs never got round to considering it..

https://atwar-game.com/forum/topic.php?topic_id=27548

https://atwar-game.com/forum/topic.php?topic_id=9910

Bearing in mind if there is 0 units in a city players can combine stacks.

Transporting allied troops should be allowed too

It seems like a good idea but open too much to abuse, mostly in scenarios.

Good idea, but imo i think that may change the gameplay too much, most of players will be afraid to attack caps ''cities'', that means, the game will lose the balance and it will be more defensive than ever before :l

You can if they have 0 inside...