General discussion about Heroes of Might and Magic II.

Perhaps someone could clarify something about battles between the computer and neutral creatures. By the way, if the computer doesn't lose, does it gain experience?
If a monster guards an artifact for the player, will that monster also guard it for the computer's hero? It seems not, because when the computer's hero was defeated and then resurrected, his experience turned out to be equal to the starting value.
And in general, I would like to hear from experienced fans of Heroes II about interesting tactics for battling neutral creatures.