Princess Erroria is the placeholder name of a female Pegasuspony with a vanilla coat, wisteria mane and tail, and blue irises. Despite her placeholder name, she is not depicted as a princess in any official material. Depending on the episode, her cutie mark is either a single pink flower, a white feather, a horseshoe, or nothing at all, and she appears as four different kinds of pony, including as an Alicorn due to an animation error. Princess Erroria also shares her design with Cotton Cloudy and "Tornado Bolt".
16:23 - talking to "Piña Colada" with flower cutie mark; 18:06 - looking at Apple Bloom with feather cutie mark, 18:44 - listening to Sweetie Belle; 19:40, 19:51 - talking to the Cutie Mark Crusaders; 20:05 - dancing with other foals
0:37 ~ 1:12 - getting candy at Twilight Sparkle's doorstep; 1:39 - walking with Pinkie Pie, Granny Smith, and other foals; 3:07 ~ 3:14 - with Pinkie and other foals; 4:16 - in the crowd listening to Mayor Mare; 4:47 ~ 6:02 - listening to Zecora's story; 6:30 ~ 6:40 - running away from Princess Luna; 7:46 - screaming and running away; 11:27 - approaching Fluttershy's cottage; 11:34 - running away from Fluttershy's cottage; 13:43 - arrives looking for Pipsqueak; 13:48 - screams and runs away again; 15:32 - in the crowd after Luna cancels Nightmare Night; 15:46 ~ 16:43 - looking sad; 18:26 - with Pipsqueak, "Noi", and "Piña Colada"; 18:42 - listening to Mayor Mare; 19:03 - approaching Nightmare Moon statue; 19:14 - hears Luna's voice; 19:27 - screams and runs away again; 19:55 - hiding from Luna; 20:54 - giving candy to Luna (all appearances are in astronaut costume)
16:08, 16:17 - at the Sisterhooves Social with Cloud Kicker; 17:22 - listening to Granny Smith; 17:26 - walking to the starting line; 17:30, 17:43 - at the starting line; 17:48, 17:51, 18:02, 18:07 - running in the race; 18:47 - beside bucket of apples
7:05 - playing on the swings with "Cotton Cloudy"; 7:23 - admiring Apple Bloom's cutie mark; 8:14 ~ 9:11 - admiring Apple Bloom's loopty-hooping; 9:02 - holding a loopty-hoop; 9:58, 10:19 - admiring Apple Bloom; 10:44 - looking toward Cheerilee and Diamond Tiara; 12:24 - watching Apple Bloom in Ponyville; 19:23 - listening to Apple Bloom tell the truth
0:11, 0:24, 0:54 - in the Rainbow Dash Fan Club; 5:03, 5:55, 6:05 - hearing Rainbow Dash talk; 6:16 - has her picture taken with Rainbow; 6:22, 6:37 - in line for Rainbow's autograph; 16:39 - dressed like Mare Do Well
4:16 - in Sweetie Belle's fantasy (Alicorn version); 9:03 ~ 9:21, 12:57 - admiring the Cutie Mark Crusaders; 11:05 ~ 11:37 - watching Twilight from outside the Hay Burger; 11:54 ~ 12:05 - admiring Twilight Sparkle; 13:16 - catering to the Crusaders; 14:19 - outside Diamond Tiara's front gate; 14:44 ~ 15:37 - part of an angry mob of foals; 16:23 ~ 18:43 - with Twilight and other foals in the Golden Oak Library; 18:45 ~ 19:09 - watching the Cutie Mark Crusaders; 19:20, 19:29 - covered in applesauce