Alright. This game is about what events will happen during this very bad war by reading the nutshell below.
In a nutshell: When Baby Mario and Yoshi destroyed King Bowser's Castle in SMA3, Bowser's father declared war on the Mushroom Kingdom.
Allies: Axis:
1) Pizza Kingdom 1) Sarassland (Renamed Dragoonland later)
2) Mushroom Kingdom 2) Koopa Union
3) Beanbean Kingdom 3) Bowser World
4) Rougeport 4) Pipe Town
5) Yoshi's Island 5) Wario Staduim Area
Now pick events on what happens.