Hello! A flash work would be the fanwork content creators create for our flash event on October 11th for OsaSuna Day! We'll release the prompts (3 themes/prompts/AUs + 1 freeform prompt) two weeks before OsaSuna Day. We're calling it a flash event because of the short amount of time in between the prompts reveal and the day content creators are expected to post their fanwork! I hope this answered your question and if not, please feel free to reach out for additional info!:)