In The Hero with a Thousand Faces, anthropologist Joseph Campbell summarized myths and literature from cultures around the world as a "monomyth"--a literary pattern that forms the basis for thousands of different stories about heroes. Campbell's work has had a tremendous influence on modern day storytellers, including Richard Adams and George Lucas.
The hero is called to adventure. S/he is tested and subjected to suffering but ultimately overcomes his/her enemies. Now transformed, the hero bestows boons upon his/her community. This archetypical hero's journey, YouTube user chowdahrogansoraaa argues, is found in the cartoon My Little Pony: Friendship Is Magic, particularly in the two-part episode "The Return of Harmony."
You can see the hero's journey almost everywhere. Most recently, I read it in Dora Saves the Crystal Kingdom, a picture book for young children.