This one is similar difficulty as the runemage except it is predominantly melee. The player has the option to choose between 2 swords and can execute combos like the warrior but it requires the use of both hands, or can choose to specialize with 2 daggers that can perform execution attacks that have massive burst damage if done right. Also both specializations have limited ranged ability by using throwing knives/stars and have a smoke grenade and minor stealth abilities.
This class is intended to be highly specialized and extremely difficult to master much like the runemage, but the sheer amount of damage the player can do is worth the effort.
I feel that players like myself that can perform melee combos efficiently and quickly as a warrior but want more of a challenge would really enjoy playing a ninja. Perhaps the ninja could be the first specialization. Like once you reach lvl 20 as a warrior you could return to lvl 1 as a ninja and face the challenges of mastering an advanced class but become extremely powerful once you become proficient.
Maybe this system can be used on the other classes as well. IE Cryomancer or Pyromancer for Runemages, Barbarian or Paladin for Warriors, Marksman or Grenadier for Musketeers, and Hunter or Longbowman for Ranger.
I would really like feedback on this idea so let me know what you guys think. Devs especially.