Here is the boss music of Mario Party 9.
Tough Enemy
Now You've Done it!
Battle with Wiggler
Wiggler's Mad!
Battle with King Bob-omb
King Bob-omb's Mad!
Battle with King Boo
King Boo's Mad!
Battle with Blooper
Blooper's Mad!
Battle with Chain Chomp
Chain Chomp's Mad!
Battle with Bowser Jr.
Bowser Jr.'s Mad!
Battle with Bowser
Bowser's Mad!
Which one is your favorite?
My favorite is Bowser Jr.'s Mad!