Woah. What just happened??? This book is a trip. I didn't realize I should've gotten some goodies from Colorado before attempting the last 25% of this book. Mind. Blown. 
 On the one hand, this is a masterfully crafted finale to the narrative that began in the Three Body Problem. New characters drive the plot, and at times this could pass as a stand alone novel. Don't fear though. Imagery and characters from the whole series make their final appearance, and the numerous plot threads are woven together into a coherent whole that is impressive. 
 On the other hand, is this a happy ending or a tragedy? Both? Neither? It's a Buddhist koan in disguise. Is it? Yes. No. 
 Damnnnnnn.