Wile E. Coyote, Yosemite Sam, or some other villainous cartoon character has decided to dispose of the Roadrunner, or Bugs Bunny, or whoever. Normal methods have failed... it's time for the Xylophone Gag. He realizes what he's doing just as he hits the high note. Blam. Often, the xylophone bars land on his head and repeat, or occasionally complete, the music line. Sometimes executed with a piano instead of a xylophone, but the results are the same -- ending with the piano's keys bouncing off the unfortunate villain's skull (or landing in his teeth). A subtrope of Musical Trigger.