Put the 5 anime of the day in order from the oldest to the newest premiere, with the ones you get right locked in place.
Put the day's 5 anime in order from oldest to newest by their premiere year.
Drag the anime (or use the ↑ ↓ arrows) and press “Check”. The ones in the right spot turn green and stay locked; each check uses up a try. You'll see the years at the end.
Challenges reset every day at midnight, Spain time (CET/CEST).
Difficulty levels
Easy:
4 tries. At least 5 years between each anime and the next. When you check, the misplaced ones get an arrow: ↑ if they go earlier, ↓ if they go later.
Normal:
3 tries. At least 2 years between each anime and the next. When you check, the misplaced ones get an arrow: ↑ if they go earlier, ↓ if they go later.
Hard:
2 tries. Anime closer in time: there may be just one year between two of them. When you check, just green or red, no arrows.