The Mongols can build:

Naptha Throwers
Steppe Cavalry
Mongol Horse Archers
Mongol Heavy Cavalry
Urban Militia
Peasants
Mongol Warriors
Swiss Pikemen
Swiss Armoured Pikemen
Khwarazmian Cavalry
Lithuanian Cavalry
Woodsmen
Swiss Halbardiers
Dhow
Baggala
Boom
Slav Javelinmen
Slav Warriors
Steppe Heavy Cavalry


It is very possible to earn tax on imports. There are two ways to do this.

1) When your trade network reaches a foreign port with a good that you don't have available in some of your provinces then the merchant in the provinces without the good will tax its import at 20% of what it would be worth to export.

2) When a foreign trade network reaches your port then your Port will tax the exports of the other country at 20% of their value. This is when you see the port having an income.