Matt Kindt & Keanu Reeves 
BRZRKR #7 (of 12) [PDF ebook] 

Diana pushes B. to uncover more about his past. Triggering a memory of WWI, where B. fights alongside his first U.S. handler, an artillery shell explosion results in a piece of B. making its way through history as a legendary artifact. Back in the present, Caldwell reunites B. with his artifact, revealing himself as the top historical expert on B. Will his proposed "Protocol X" unlock the ultimate truth B. seeks, buried deep inside his memories?