Same start-letter sequence rules, but every new letter in each valid answer is collected.
You still must start with the required letter. Completion is when all 26 letters are collected.
Play: Alfafill Hardest mode
How to play: Start from A and follow the required next starting letter each turn. Any valid submitted country collects all its new letters. You win when no letters remain.
Remaining letters:26
Highlighted letter on the grid is your required next start.