Not next time, @TwilightCurse. It's acctually a pretty fun idea for a kata, take into account the suggestions and edit it, such as adding random tests, improving the description an you'll have yourself a cool kata. 😁

For instance, in Codewars tradition, you can add some lore to the description, which will make it easier to understand, e.g.:

"There is a children's game in which someone, such as a person, country or other entity, is chosen as a tyrannical ruler who loves to ban the letters on the alphabet until a single letter remains. The children take turns stating the banned letters, but they cannot use the letters that were already banned, etc......"