Twilight: The player; trying to focus amidst distractions.  
Fluttershy: Pac-Man; fitting, since she’s the yellow one… That’s pretty much it.  
Rainbow Dash: Clyde; seems to be unable to find Fluttershy. Clyde is the one that wanders randomly. If you die because of Clyde, it’s pretty embarrassing.  
Pinkie Pie: Blinky; Blinky follows Pac-Man’s path in an attempt to catch up to him. Pinkie is shown here holding up an airhorn in an attempt to surprise Fluttershy from the back.  
Rarity: Inky; Inky has a sort of unpredictable pattern. Inky randomly decides to either follow Pac-Man or catch Pac-Man off guard by rushing in front of him. This is why Rarity is shown upside down and with a goofy look on her face, she’s trying to look random! I’m surprised Pinkie wasn’t chosen to be Inky…  
Applejack: Pinky; Pinky always tries to catch Pac-Man off guard by positioning herself in front of them. Applejack is probably using her hat as bait in order to lure Fluttershy to her.

Rarity’s face tho

@numbah1  
I was thinking they were probably the other ghosts, but what’s really got me confused is why Rarity is upside down and what AJ is doing with her hat.

@Flying Pancake  
Rarity and AJ appear to be the other two ghosts, with AJ being Blinky and Rarity being Inky.

Reminds me of Wreck-It-Ralph.

I’m confused….

I’m a little bit lost; I get that Twilight’s playing, Fluttershy is Pac-Man, and Pinkie and Dash are Pinky and Clyde, but what are Rarity and AJ doing? Also, is there some larger context to the story here I’m missing?