Robby made six-sided dice featuring the cutie marks and colors of twelve ponies.
Back row, from left to right: Rarity, Rainbow Dash, Twilight Sparkle, Applejack, Fluttershy and Pinkie Pie.
Front row, from left to right: Celestia, (I don't know), Bon Bon, Lyra, Derpy and Luna.
That's right. I can't identify a cutie mark on sight. And, yes, it's embarrassing.