A very captivating story and all the plotting and ruthlessness in the persuit of power seeing sisters and turn on each other. Even children are killed if they post a threat to another succession to the throne. We also see the very good and as well as the grossly incompetent and fools rise to the throne (although few would match Caligula or Nero, the ultimate Roman tyrants)
Chinese historical drama seem to follow the familiar pattern of coughing blood when they are sick or distressed.
But the English captions are poor and hard to read against screen image backgrounds so they should be inserted in white letters over a black band. Relying on complete direct complete computer translation is unreliable at best and in many cases nonsense (eg Crown prince translated to Prince Edward. Even with thinking I sometimes cannot work out the gist of the dialogue . Also we don't know the history of the kingdoms and so and little explanation maps etc would also help to explain the historical context even if the story is not entirely true