The character Dev Fleischman -- author of a scholarly text on the Fillory books and their author, Christopher Plover, and seen in the video that Quentin shows Alice -- is played by Lev Grossman, the real-life author of The Magicians trilogy on which this series is based.
Eliot says "avada kedavra" when he wants people to leave the room. This is used in the "Harry Potter" series to kill instantly.
Kacey Rohl and Adam DiMarco dated for several years. They played Marina Andrieski and Todd respectively.