Ender's Game series

Ted Chiang's Stories of Your Life and Others is the best, single-author collection of short stories I've ever read. If you like that, you might also enjoy The Lifecycle of Software Objects, an absolutely heartbreaking novella about simulated children, and his follow-up collection Exhalation. Orson Scott Card's Ender's Game is fantastic, and it's follow-up, Speaker for the Dead is even better, and my favorite science fiction novel of all time. They won back to back Hugo and Nebula awards. Card is a polarizing figure for his outspoken political opinions, but if ever the art should be separated from the artist, it's Speaker, which is an incredible exploration of empathy and responsibility, in addition to being a gripping, action-packed, science-literate read. Many more in this series, if you get into it.…

The Ender's Series - For the essence of xenophobia and subjective realities.

In Ender's game they are searching for the perfect specimen to transform into the perfect military commander. Very smart men are making elaborate plans how to entrap him in order to mold him into a lethal machine. They are searching for a commander who can end (not intended) unresolvable conflicts decisively and, above all, permanently. Not for a morally balanced/superior leader. Anyway, I read Ender's game first when I was young and I loved it for the action, mixed with philosophy. Now I enjoy the rest of the books a lot more then the initial one.

Pathfinder - Orson Scott Card Not only is it written by the author of the epic ender's game series ( which is a must as well), but it mixes genetic mutations of time control, ancient(objectively, not subjectively.) civilizations and plain ol good sci-fi together for one hell of a ride.