Michelle Paver - Gods and Warriors #1 EPUB

Young Hylas--goatherd, Outsider, thief--is hunted by powerful warriors who want him dead and have kidnapped his sister. Hylas is forced to flee his home, but not before a mysterious stranger gives him a bronze dagger. While on the run, Hylas must use his skill and wits to survive a shipwreck and a great white shark attack, befriend a dolphin, and help Pirra, the runaway daughter of a High Priestess. Together with Pirra, the dolphin, and the valuable bronze sword, Hylas fights to discover why he's being hunted and find his sister before the warriors find them.