Reading Edmund Spenser's the Faerie Queene in English class is amusing. Mainly, because there's a part where Spenser takes time out to describe what each of the Seven Deadly Sins look like in excruciating detail. I chuckled, going, "Yeah, you and every Deviantartist ever! Wait a minute..."
So I decided to compile a Definitive List of all the things which every Deviantartist MUST draw at some point in his or her career. I shall then, in fulfillment of this trope, do an illustrated version myself.

EVERY DEVIANTARTIST AT SOME POINT DRAWS:
1. The Seven Deadly Sins
2. The 12 Signs of the Western Zodiac
3. The 12 Signs of the Eastern Zodiac
4. Alice in Wonderland
5. Personification of the Four Elements
6. Personification of the Four Seasons
7. Jack Skellington
8. One Anthro
9. One Woman of Improbable Physique

And, if you're really ambitious, and very sure of your skill as an artist, a worker, and a creative person, you will draw

10. Two or three Enigmas of the Major Arcanum of Tarot, before you get bored and quit.

And that is it! Definitive!
Well, if you can think of any others, do add them in the comments!