Princess Pony Head is the ultimate party princess. She is loud, abrasive, eccentric and full of energy that she cannot wait to exert. She considers herself to be perfect and well liked by everyone, though several episodes imply that most people find her annoying. She can be pretty inconsiderate of others, especially those she dislikes. Pony Head will put her own needs and wants over others, but depending on their closeness, such as with Star Butterfly her best friend, she will shift her attention to help them, though this has been shown to be difficult for her.
Pony Head is surprisingly intelligent to a certain degree. Whenever she has a plan, she will go to great lengths to bring it to fruition. This of course results in her unintentionally concerning others. The most notable example being in "Queen-Napped" where despite her malformed execution, she was able to get people to like Eclipsa through her rather outrageous plan of "kidnapping" her for a live streamed show.
Above all else, Pony Head believes that she needs to be the center of attention and will actually become annoyed or saddened if no one is paying attention to her. After her horn gets damaged in "Skooled!", she becomes morally depressed and refuses to listen to anyone. It is only through watching a Korean drama and getting upset over how it turned out that she overcomes her depression and gets a 3D printed horn to replace her old one. Despite all this, Pony Head is very loyal to Star and will aid her and her friends when necessary.
True to her name, Pony Head is a floating light blue colored horse head, or rather unicorn head as she has a dark teal striped horn. Her mane is pink and she has a small heart birthmark on her neck. She has giant white eyeballs with blue irises and yellow star shaped pupils. Her bottom is actually a hole that can carry items like a back pocket as revealed in "Goblin Dogs".
- Pony head was based on old drawings made by Daron Nefcy.
- Daron's early drawings of Pony Head were a lot more disturbing compared to the character seen in the show. Pony Head was initially drooling constantly and had blood dripping from her neck.
- According to Star and Marco's Guide to Mastering Every Dimension, Pony Head is the oldest of thirteen sisters.
- In "Bam Ui Pati!", Pony Head is revealed to have been born on August 4, 2001. If the episode took place on March 31, 2018 (the day the episode aired) that would mean that Pony Head is 16 years old, just one year older than Marco and Star.
- Daron Nefcy confirmed in a Reddit Q&A that Pony Head's mother passed away sometime prior to the series beginning.