The Tower of Ninjas is the home of the Black Dragon Ninjas. It is located in the northeast region of the Border Zone. This location can be discovered by reading a Tech Hunters Map.
Upon entering the tower, the Black Dragon Ninja faction becomes hostile and attacks; they will, however, also attack mobs like Dust Bandits, so you can lead a group in to help. The layout of the tower is very similar to that of a Shinobi Thieves tower, with Black Dragon Genin manning four crossbow turrets on the roof.
The location is home to Dimak and Buzan, the leaders of the faction, both of whom are wanted by The Holy Nation with a 20,000 cat price on each. Dimak wields a Meitou quality Ninja Blade.