Whether or not we consider the Christ-like heroic, there can be no doubt that the label existential is thoroughly appropriate. The Christ-like Prince Myshkin is an existential hero, and an existential Jesus Christ was the primary inspiration for Soren Kierkegaard, the father of existential philosophy.
Rather than Christ-like, I would prefer to call Prince Myshkin a true Christian, in the same vein as the awesome, existential giant Brand from Henrik Ibsen's play of the same name, written three years earlier. The Norwegian Ibsen and Dostoevsky were, of course, heavily influenced by the Danish genius, who died a decade earlier aged 42. Incidentally, Jesus, Myshkin and Brand all come to a tragic, yet inspirational, end.

