Where is the artificial intelligengence?

[Unconquered Sun]

How effectively a 1UPT game?

In Civ 1, when a stack outside a city is attacked, it chooses its best defender: but if he loses the entire stack dies no matter how many units in it.

So, overstacking near a (potential) frontline could result in what's best described as the game equivalent of the first few days of Operation Barbarossa.