Challenges
Closed runs with a fixed list of countries instead of endless questions. There are three: Remote Island, Giants of the World and the Time Trial with flags or outlines.
Which challenges there are
Remote Island: the flags of island nations, from the Caribbean to the Pacific, plus islands from Europe, Africa and Asia such as Malta, Mauritius or Japan. Giants of the World: the flags of the largest countries by area, from Russia to Peru. Time Trial: 60 seconds to name as many flags or outlines as you can, from a random set of 50. All three are in the Play tab.
How to play
In all three you see a flag, or an outline in the Countries time trial, and type the name of the country. You can use the keyboard or tap one of the suggestions that appear as you type. The Pass button counts as a mistake. When you get one wrong, the game shows you the right answer and moves on: nobody throws you out for a mistake. Remote Island and Giants have no clock; in the Time Trial the clock is everything.
Scoring and rewards
Each right answer is a point. Finishing a run with at least one right answer earns coins, a wildcard for every 5 right answers and that challenge's achievement. Finish without a single mistake and you also get extra XP, plus two more wildcards in Remote Island and Giants. Each challenge keeps your best score and has its own ranking, where ties go to whoever was faster.
Challenge a friend
At the end you can send a challenge link. Your friend plays the same questions in the same order with your score as the target, and the game tells them at the end whether they beat you.
Tips
In Remote Island the hardest ones are in the Pacific: Tuvalu, Kiribati, Palau or the Marshall Islands. Go over them on the Oceania flags page before you play. In the Time Trial, start typing and tap the suggestion as soon as it shows up; three or four letters are usually enough.
What you learn
Remote Island covers exactly the flags you rarely see in other modes, and Giants is a good first step for beginners. The Time Trial trains something else: recognising instantly, without thinking, which is what decides duels later on.