The biggest increase.

It’s very likely that the Fortress will win due to the Cows, which remove one unit of tier 7 from the battle, plus the Hydra does a lot of damage in mass battles. However, the Castle will probably lose to the Fortress in terms of weekly growth. As for the Stronghold, I’m not sure. The Conflux isn’t that strong with only one growth, yes, it has the first move, but what happens after that is unclear. I’m not sure if the Tower can do anything significant against two combat stacks without morale/magic. A lot will depend on the tactics, as mentioned earlier, but it’s also worth considering the army bonuses, such as Inferno having two retaliations, for example. But for some reason, it seems to me that the Fortress has very good chances under these conditions. I wouldn’t bet on the Conflux at all, due to its too weak units, even if there are many of them. But the Necropolis is definitely last.