Zen Buddhism in Korea is called “Seon,” and it is characterized by a strong focus on asceticism. This is the practice of denying oneself various pleasures (or sometimes even necessities) in order to focus more completely on one's spiritual work. Asceticism is found in all forms of Zen, but Seon in particular puts a lot of focus on it. Seon monks are frequently hermits, living a self-denying lifestyle in order to focus completely on enlightenment.
Interestingly, while Japanese Zen temples were heavily involved in supporting and legitimizing militarism and imperialism in the years leading up to World War II, Korean Seon monks were often prominent in the resistance movement. This doesn't mean that Seon is somehow more virtuous than Zen- it's just that organized religion in all countries generally acts in support of the status quo. That's why, in modern America, fundamentalist Christians are among the most conservative people in society, and tend to strongly support the military. Similarly, Zen priests in Japan supported their own military government, while Seon priests in Korea were active in defending Korean tradition from the invading Japanese.
Seon is still a large and active sect in Korea, and has recently spread to the West in various forms.