Andy Diggle 
Expanse, The: Dragon Tooth #4 [PDF ebook] 

The first lore-expanding arc of the Kickstarter sensation comes to an explosive close! Working together, Avasarala and Drummer piece together the true nature of the mysterious "Dragon Tooth" The Rocinante joins a battle group of OPA pirate-hunters for a final showdown with the notorious pirate Sohiro, but they get more than they bargained for! But it’s up to The Rocinante and its crew to secure the alien Ring Gates-and the future of the human race