Id: 94261859
I wanted to make the difficulty somewhat consistent with:
easy-hard-easy-hard-easy
They are separated with certain parts of the song.
Cube part is supposed to be kind of easy. First wave has two parts. First part is hard while second part is easy. The ship is supposed to have some tight parts and be pretty hard. The last wave is not supposed to be very difficult, but enough to bring a satisfactory ending.