You get the objective to reach Infamy Rank 2 during Episode 3 of Maneater.
Go to the Infamy tab in the main menu to check your Infamy Level and Infamy Points. You get infamy points by killing bounty hunter boats. Kill Humans to attract bounty hunters. Once bounty hunters appear start killing them to earn Infamy Points. When the Infamy meter fills up your Infamy Rank increases and it brings out the Hunter Leader.