1.60. Abel walks out of the ocean. Cain asks him who
he is, and Abel answers. Cain kills Abel. (MWD original)

1.60 answer: Abel is a prince of the island nation that he landed on. A
cruel and warlike prince, he waged many land and naval battles along with
his father the king. In one naval encounter, their ship sank, the king
died, and the prince swam to a deserted island where he spent several months
building a raft or small boat. In the meantime, a regent was appointed to
the island nation, and he brought peace and prosperity. When Prince Abel
returned to his kingdom, Cain (a native fisherman) realized that the peace
of the land would only be maintained if Abel did not reascend to his throne,
and killed the prince (with a piece of driftwood or some other impromptu
weapon).