Mountain yam (yamaimo) is often grated, resulting in a slimy substance known as "tororo." But when cut in cubes, it can make for great kimchee, also (like how one would have kimchee cubed radishes, a.k.a. "kkakdugi"). When cut in cubes, mountain yam has another interesting texture that's hard to describe. It has a wet crunch, for lack of a better term, that's very refreshing, and in my opinion, mountain yam is especially good in summer.
One of the most classic dishes prepared with mountain yam is "maguro yamakake," in which the tororo covers raw tuna.