Dinky Doo

Dinky Doo is the placeholder name given to a filly unicorn seen in several episodes engaging in activities with her friends. Dinky has a pale purple coat color, a blonde mane, and yellow eyes. Her eyes are of the standard adult mare model, rather than the filly one. She has sported many cutie marks including a pillow, an archer's bow, a horseshoe, a pair of dolphins, and sometimes no cutie mark at all. She shares her design with Berry Pinch and Tootsie Flute. Dinky appears several times in both seasons one and two as a non-voiced background filly.

Depiction in the series
Dinky is often a crowd-filler. She makes her debut appearance in Winter Wrap Up, jumping up and down while singing the song. In the next episode, Call of the Cutie, Dinky is shown multiple times, although in each shot Dinky has a different cutie mark. Dinky Doo appears in Lesson Zero in Magic Kindergarten during Twilight Sparkle's visualization. In Luna Eclipsed, she is dressed as a firefighter for Nightmare Night. She has her photo taken with Rainbow Dash in The Mysterious Mare Do Well while wearing Rainbow Dash fan-gear. When Pinkie Pie says: "Anypony else wanna panic with me?" in It's About Time, Dinky is in the crowd of ponies Pinkie addresses.

She also appears as one of Apple Bloom's classmates in season two. In The Cutie Pox, she stares in awe at Apple Bloom's loop-de-hoop skills, and in A Friend in Deed she's playing with Scootaloo and two other foals.

Dinky appears with the adults Golden Harvest and Written Script in The Last Roundup. Both are looking down at her fondly as she looks up at Written Script. She then boards the train to Canterlot with Golden Harvest.

Dinky is also with Amethyst Star in Sisterhooves Social. The two of them compete in the titular Sisterhooves Social. Together they are given a ribbon in the pie-eating contest and pig contest. In the race, they take the lead at the box vaulting but lose it at the pie-eating to Rarity and Sweetie Belle. They somehow regain the lead in the race and reach the grape-squishing stage first, but end up losing this stage too.

Appearances
Times are approximate and taken from videos with no prolonged transition for commercial breaks.

Other depictions
Dinky Doo appears in in Gameloft's mobile game as a playable character, called Fire Chief after her attire. with the description "Fire Chief is a unicorn filly who's always on a roll and off to the rescue!" She was made available in response to fan request.

Merchandise
She appears along with Derpy on the fan-designed WeLoveFine T-shirts "On a Roll" and "To The Rescue", both of which are by the same artist. "On a Roll" features her atop Derpy along with a host of characters from the show, while the formerly available "To The Rescue" features her falling away from Derpy. Neither of the designs refer to her or any of the other characters by name, though the former keywords of WeLoveFine.com's page for "To The Rescue" included "dinky doo".