Ninjutsu
Perhaps, this is the most popular martial arts in pop culture. If you know the term Ninja, then they follow this martial art as their fighting style. It is dangerous in a sense that it is only used as an unconventional fighting method. You also notice that ninjas usually cover their faces with only their eyes visible. This is because it is usually used for espionage and assassination attempts. Ninjas are technically called hinins or non-humans because of the nature of their job.
