The computer only plays Huns , and you cannot be Huns.
Settings must be in Post Imperial Age and hard/hardest difficulty
Copy these 2 files , akal.scx in scenario folder , and the empires2_x1_p1.dat in Data folder .( don t forget to backup the original file first)
The computer cheats in a diferent way , you will find how. Anyway is possible to beat him but you need all your energy , so it becomes a very interesting game. In the beginning you need to survive his rush ,after that do your best.
Enjoy