Playing the Boos

Continuity

 * Operetta has a poster up of Crescenda von Hammerstone, her idol whom she got to meet in "Hickmayleeun".

Milestones

 * Johnny Spirit makes his cartoon debut.

Other

 * "Playing the Boos" was initially scheduled for a dual release with "Inscare-itance" on December 5th, but wasn't uploaded until the tenth on the Monster High website, which coincided with the addition of the first five Volume 4 webisodes to the website.
 * "Playing the Boos" was announced as "Spirit Without a Cause", a reference to the 1955 USAmerican movie Rebel Without a Cause.
 * Upon his transformation to Holt Hyde, Holt uses the same animation as he used for that same occasion in "Here Comes Treble".