Unlike in Achilles where jumping is useless, in this game people have overlooked the reason why it actually has a use. The various mounted units in the game that everyone says are "rediculous" to fight can't pivot, and can only attack in front of them. Jump in the air on the aproach, land on them slashing, and they die easier than any other unit in the game, even in groups.
I find it amusing how many people repeat the statement "Balloon Invasion is a lot like Gemcraft" when Balloon invasion arrived first. Its the same as saying "The Empire Strikes Back is a lot like Return of the Jedi"
The game is 'playable' if you account for the mistakes, odd luck, and AI movement. The AI will not form treaties, they generally form cold wars. One goes to defend an area it likes, and the rest come and send troops due to what it feels are invacion threats. The result of this is that if you keep even an army 1/5 of the size of the massive army on the border, they don;t attack. Sweep around and take all the other territories you can, and then use your 20 to 4 troop production to whittle them away. I beat the game like this.
 "Warlords: Heroes"){kind=icon}
 "Vector Runner"){kind=icon}
 "Balloon Invasion"){kind=icon}
 "Sensou"){kind=icon}