Expert Collector of Blue Cubes Expert Collector > Page: 14 Acquiring Req.: Collect at least 50 Blue Cubes. Reward: When collecting Blue Cubes, the Collectable Item is doubled. Blue Cube Lv 15 Blue Cube's Natural Enemy Natural Enemy (11-20) > Page: 3 Acquiring Req.: Kill at least 27 Blue Cubes. Reward: Killing Blue Cubes grants you bonus XP. Blue Cube Lv 15 Legendary Blue Cube Hunter Natural Enemy (11-20) > Page: 3 Acquiring Req.: Kill at least 63 Blue Cubes. (Blue Cube's Natural Enemy Title is required.) Reward: Killing Blue Cubes grants you bonus XP. Blue Cube Lv 15