Third Way of Ten tactics for Uncovering Kakashi Mask

3.    Face washing in constrain 

This tactic takes effect only by emotional people such as Naruto. His definitely will wash his face if the mask is dirty. Who does wash the face by wearing the mask? However, we need to ask the Shikamaru about specific implementation steps.

Advantages: His true face would be appeared by 100% possibility once the tactic is successful.

Disadvantages: Kakashi has flexible bodywork and more flexible mind, the success chance is uncertain.