June 3rd - Goat-ertainment - another puzzle!

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My goat-goal this month is to post something interesting every day of my goat-dom.

Today I have another puzzle for you! Here are the rules:

  1. I don’t care if you break the rules.
  2. Send me guesses via whisper, so other people get a chance to figure it out.
  3. There is no prize.
  4. Did I mention there’s no prize? Well, there’s no prize.
  5. It may take me a little while to reply to your whisper, so don’t freak out.
  6. I might post hints in the comments.
  7. Feel free to discuss in the comments, but try to avoid spoilers if you can. If you definitely don’t want spoilers, don’t look at the comments.

Now, here’s the puzzle! There are five boxes below that represent the middle of a long sequence; you probably see elements of this sequence frequently, but might not think about it.

What pictures might go in the box with the ???, and why? Whisper me your answer!

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