Chibi Theater: Fly, Cadets, Fly!

Monster Character Theater- Fly! Trainee Corps (ちみキャラ劇場 とんでけ！訓練兵団) is a series of flash animated gag shorts included with each Blu-Ray Disc/DVD releases of the anime featuring the characters of Attack on Titan in chibi form based on designs by Yuupon.

Trivia

 * These shorts feature the Japanese voice actors from the anime in their respective roles


 * There are a lot of running gags throughout episodes:
 * Eren over-sleeping, causing him to be late and get mad at Mikasa/Armin for not waking him up
 * Members of the cast getting eaten by the Colossus Titan at the end of each episode (with Eren almost always being one of them, usually making excuses as to why he got eaten, and then arguing as they slowly sink)
 * Mikasa never making facial expressions, changing her tone or showing any emotions at all
 * Keith getting mad at one of the cadets and telling them to come to his room later
 * Mikasa showing feelings for Eren, only to be turned down by him
 * Armin being a big pervert


 * Characters always pronounce sounds or small movements they make (ex. saying chung* chung* when the bell is ringing, wipe* when they are wiping tears, saying raise* while raising their hand, or dot* dot* dot* ding* while thinking)


 * There are a lot of references to anime episodes of the series:
 * The first day of training when they got intimidated by Keith Shadis
 * Jean getting captivated by Mikasa and her long black hair, and developing a rivalry with Eren
 * Mikasa cutting her hair, saying how "the world is a cruel place" (but for a comedic effect), shoving a loaf of bread into Eren's mouth, telling others how she is way stronger than them
 * Sasha stealing meat and can always be seen eating a potato
 * Armin bringing a book and reading it with Eren, later mentioning "burning water, frozen earth, fields of sand" (although in different context)
 * Levi Ackerman dressed up in his cleaning outfit and carrying a mop, "taking cleaning very seriously"