I'm new to this whole modding thing, and dont know what is possible yet.

1. Is it possible to spawn units (or buildings) into the game besides at the the beginning (startpos)?

2. What controls birth of children?

3. What about the arrival of the mongol horde? is this event hardcoded, or is it available somewhere?

i can see many nifty areas to mod here, but this sinking feeling in my gut that tells me this stuff is unalterble.