In this video, piano teacher and Musiah inventor Brendan Hogan plays the well known piece "Sorrow" by Hungarian composer, Bela Bartok — with an original orchestral accompaniment composed and arranged by Brendan himself.
This particular piece is Piano Lesson #112 from the Musiah Online Piano Course which features lessons for beginners, mid level and advanced students. "Sorrow" is from Level 9 of 13, so it is quite advanced.
One of the main challenges of this piece is that each hand has to play quite different phrasing to the other hand - at the same time. So it is a great piece for helping you develop split concentration (the ability to think of and do multiple things at the same time).
Note: Brendan has posted a number of videos like this one to demonstrate some of the more advanced pieces on the Musiah syllabus. In the future, these videos will gradually be replaced by student videos as more videos from advanced students are received.