A lot of the WoR stuff are optional though, but then again it would be pretty hard to go through the last dungeon if you don't do most of them.
-Gang Starr / Nujabes blend - https://youtu.be/lsci1vu6ickDOOM Tribute - https://youtu.be/qmBQ2BDefKMDonut of the Heart cover in Javascript - https://youtu.be/afLc2CkC8lk