It is possible to have an army attack any human-owned province on turn 2. How to do this:
1) Select a province, via #setland if you want the original defenders attacking (in addition to the ones you set)
2) If you want the attackers to be independent, add them before defining any owner for the province. You can add multiple commanders, give them items/units/bodyguards, name them, etc.
3) Set province owner via #owner command. Set the second army. Repeat 3 as many times as you wish, always changing the nation. The last nation will start as the province's owner, and will have the forces you defined after the last #owner command. Next turn, all the other forces will attack that province.
As far as I know this isn't used in any map, but it could make an interesting addition to scenario description. As an example, a scenario of the fall of Ermor could have weak-ish undead forces attacking all provinces. Ermor would have enough money to build temple into each province it caught, because it would get income from them for as long as their dominion doesn't touch that province. And after the temple has been build, their dominion will spread.... Imagine miniature Ermors breeding all over the map like cancer.