Pretty simple. Choose 2 civs you think have bonuses which combine and would make an unbeatable civ. There are only 2 limitations: you have to choose only 1 of the unique units and 1 of the team bonus; the other will be just a standard bonus.
I'll start with Mongols and Huns:
- no houses
- op hunters
- faster stable
- cheaper and faster firing ca
- that trebuchet bonus huns have I don't remember
- higher light cav/ hussar hp
Unique unit: Mangudai
Unique tech: the one which makes siege faster
Team bonus: higher los on sc
PS: feel free to use WK civs as well!
I'll start with Mongols and Huns:
- no houses
- op hunters
- faster stable
- cheaper and faster firing ca
- that trebuchet bonus huns have I don't remember
- higher light cav/ hussar hp
Unique unit: Mangudai
Unique tech: the one which makes siege faster
Team bonus: higher los on sc
PS: feel free to use WK civs as well!