This is of their original characters, Demareter and Persepony!
Here's what they have to say about these two.
Demareter is an Alicorn Goddess, a Hippotheos (hippo- Greek for horse, theos- Greek for god or deity). She is a Pony-ized version of the Greek deity Demeter. She is often considered a fertility goddess. She presides over agriculture itself (grains, bread, and the harvest in general), the general fertility of the earth, the cycles of plants and seasons. Demareter is basically “Mother Nature” and sometimes referred to as The Great Mother. She is also goddess of sacred law and the cycle of life and death. She has given part of that last domain to her Daughter, Persepony. Demareter acts motherly toward all others unless her or her daughter are hurt or threatened.
Persepony is also an Alicorn Goddess, a Hippotheos. She is a Pony-ized version of the Greek deity Persepone. She is also considered a fertility goddess. She presides over the season of spring, and over the dead (being the Queen of the Underworld). She is a living example of youth, beauty, and life.
There were only descriptions to start with so it took a bit to design them. I think they turned out well.