this chart definitely has some gimmicks, but they’re good gimmicks that fit the song well. it’s really fun actually, especially that section in the middle with the freezes. took me forever to get decent scores on this song without bar, finally got an A :D
It's mostly BPM changes and stops, especially those that are added for the sake of increasing the song difficulty. (For example this song maintains a contant bpm but they double it and halve it numerous times).
Funny how the lower 3 levels are so hard for their rating that they should be bumped up by 1 level (should be 7, 11, 13) while Expert and Challenge are on the lower end to their level rating (15, 17)