The Master Lightning Bolt (Book 3 of 4 War on the Gods)

"For too long you've wasted your potential. Moping about. Feeling sorry for yourself. It's time you channel your feelings into something worthwhile."
After years of struggling to choose between duty to his gods and loyalty to his friends, Karter, Son of Zeus finally has the decision made for him.
Not only have the gods killed everyone he loves most, but his father has also received visions that Karter is meant to execute Diana, Daughter of Apollo. Apparently, when he does so, the war on the gods will end in Zeus's favor, and, as a reward, Karter will be made into an immortal among the rest.
For a while, this seems like the perfect solution to Karter's problems. After all, what he wants most is to forget his agonizing past and move toward a brighter future. But as he spends more time on Olympus, he begins to realize pain may not be so easily buried...
Karter will have to face the choices he's made—and the gods...