Respawn: 18 and Up (Respawn LitRPG series Book 3)

Targets come in all kinds. Some fall prey to those holding a gun for the first time. Others cannot be defeated even by the most experienced shooters in the world, unless their luck comes to save the day. Cheater’s accuracy is unparalleled, and Lady Luck is on his side. He has all the marks of a champion, and champions never miss.
The true aim of his heart, though, is not one that can be hit with a single fortunate shot. No, she is far to the west, beyond several of the Continent’s most dangerous locations: the bleak boundaries dividing regions from one another. Solo veteran immunes are little more than clumsy chunks of meat in such places, never mind brash newcomers like Cheater.
But Cheater’s not going solo. He has an experienced friend. But loyalty is hard to verify, and you never know when a friend might disown you simply for failing to complete his task by its deadline.