Yes, 闯关鸭 is free to download, however it contains in-app purchases or subscription offerings.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
闯关鸭 has several in-app purchases/subscriptions, the average in-app price is 77.25 H$.
To get estimated revenue of 闯关鸭 app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.