Heroes 5.5 WarGame Edition - Tactical Edition.

It won't work properly. You can set the upgrade automatically when a building is placed, but in that case, we'll get +2 to the city level and lose the ability to upgrade it further (i.e., improve creatures).

Is it possible to make it so that the building or the automatic upgrade doesn't give +1 to the castle level? In principle, +2 to the level isn't such a big problem; it can be balanced. And then, why would we need to upgrade creatures? Let's get all three upgrades and the desired growth rate for balance right away.