How does Mongolia's UA work?

[suvin123]

What does 'exacting tribute' means? I can't annex city state even though i demanded tribute from them.

 

[Gazebo]

What does 'exacting tribute' means? I can't annex city state even though i demanded tribute from them.

When you click on the 'demand tribute' option in the CS window, the 'enslave a worker' option is replaced with an 'annex city-state' option. If you can do it, you get the CS.
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