Liu Cixin brings in loads of original ideas and executes them with equally original thought process. Death's End is the most difficult book of the trilogy; its verbose, back references the first two books often. 
 The strength of the book lies in its ideas. Cixin explores Universe in an unconventional fashion. He takes a step further and writes about humanity from the perspective of an advanced alien race. The result of this observation is deeply saddening. This part of the narration is by far the most brilliant piece in this series. 
 This has been one of the most enjoyable series in recent years.