Boogie Up: Hard+ is the second stage in Boogie Awakens! Stages.
Battleground
The base will spawn Gato Amigo at a fast rate, and when you touch the base a Bore and an Angelic Sleipnir will come out. The Bore is buffed 220%. Bores now spawn at a medium rate, and 1 Sleipnir will come out every 2.5 Bores that spawn.
Trivia
There is actually a mistake inside the stage on the top left corner. It should say "Boogie Up (Insane)", but it is actually labeled "Oh Yokozuna! (Insane)", which is the name for the Sumo Awakens stages.