A character to match this song: https://www.youtube.com/watch?v=8ATu1BiOPZA

She has no name, she's only called the Queen of Corruption and Greed.

Once a ruler of a kingdom in Equestria, she was one of the most selfish ponies alive. Killing ponies, and taking their belongings for her own gain. Celestia finally banished her to a place that pained her, her cries always being heard through out the land. It was until a spell finally shown the true greedy monster she was, as casted by Starswirl himself. Her eyes turn gold, along with her hair, so she could only see gold and not be able to differentiate anything like a pebble, from gold. Her mouth was sealed shut so no one could hear the screams. The crown she had was taken and is now in a museum.

Everyone had forgotten her true name as well, most know her as a fake mare only told about in stories to scare young ponies into being kind and unselfish. But they don't know that.