Ragnastrike Angels

Anime
To publicize the game, a micro-anime of 12 episodes of 30 seconds each was produced (25 seconds of history and 5 seconds of advertising). In total (ignoring advertising), the anime lasted 25x12=300 seconds (ie: 5 minutes).
 * Main article: Ragnastrike Angels (anime series)

Source

 * https://myanimelist.net/anime/33021/Ragnastrike_Angels