Expert Collector of Black Assassin Sentries Expert Collector > Page: 35 Acquiring Req.: Collect at least 50 Black Assassin Sentries. Reward: When collecting Black Assassin Sentries, the Collectable Item is doubled. Black Assassin Sentry Lv 41 Black Assassin Sentry's Natural Enemy Natural Enemy (41-50) > Page: 9 Acquiring Req.: Kill at least 132 Black Assassin Sentries. Reward: Killing Black Assassin Sentries grants you bonus XP. Black Assassin Sentry Lv 41 Legendary Black Assassin Sentry Hunter Natural Enemy (41-50) > Page: 9 Acquiring Req.: Kill at least 308 Black Assassin Sentries. (Black Assassin Sentry's Natural Enemy Title is required.) Reward: Killing Black Assassin Sentries grants you bonus XP. Black Assassin Sentry Lv 41