This is an archived problem from a previous year. Submissions are closed, but you can view the problem and its solution.
You're at your local North Pole pub for a friendly game of chess, and you notice your opponent, one of Santa's elves, has an unusual strategy: he mirrors every move you make. If you start with 1. e4, Mr. Elf will respond with 1... e5. If you then follow up with 2. Nh3, he'll respond 2... Nh6.
Not wanting to upset an elf right before Christmas, you decide to avoid making moves that would prevent him from mirroring (except for the mate, of course). For example, after 1. e4 e5 2. Qh5 Qh4, you wouldn't play Qxh4, since that would be impossible to mirror.
Given this situation where your opponent is committed to mirroring your every move, can you, as White, find a way to give checkmate with your rook (an original rook, not a promoted one) on move 6?
Give the whole series of moves. There should be 6 moves for White, and 5 for Black.
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