Ninja and Kunoichi can scout, spy, sabotage, and assassinate.
Ninja and Kunoichi are the only player classes that can assassinate other players and thus cause destruction to armies and ultimately the enemy clans that own these armies.
Ninja and Kunoichi can burn buildings in a town. They can also destroy castle gates and thus temporarily lower castle defense.
Ninja and Kunoichi may spy on armies of opponents. When Ninja or Kunoichi are located at the headquarters of an opponent, they can reveal more information about the opponent.
Ninja and Kunoichi may scout an area, as they are not impeded by a zone of control of a rival army. They can therefore effectively see through the fog of war on the map.
When Ninja or Kunoichi are within an enemy area, they can take on disguises. Ninja can be seen on the map by rival clans as Komuso or Yamabushi. Kunoichi can be seen on the map by rival clans as Miko or Geisha.