To use any of these costumes, you simply type them in when creating a character. No spaces, no need for capitalization, just type it exactly as I've spelled it.

Type in "jessecox"

Type in "darkjesse"

Type in "markiplier"

Type in "pinkmark"

Type in "jimsterling"

Type in "thearistocrat"

This is not a comprehensive list, this is merely a list of all the ones that I personally have found or been told. I made this because I could find no such list online, especially not one with images. If anyone else finds a costume, please let me know and I will add it to the list!

Credit for finding the alternate costumes of Jesse, Mark, and Jim goes to TeaPayne on this forum post. (While he also technically discovered the others as well, I did not learn about them from him, but rather found them myself.)