Start with 1e4 ,then look for a good opportunity to put one knight on f3 and the other on c3. Ask me this question in class, please, and I will have a more thorough response.
Sorry about taking so long to answer. I wasn't checking this spot. I will be more prompt in the future.
It doesn't have to be a pawn, though that is the easiest and most common. As long as White (assuming White is sacrificing) can control d6 and f6, the sequence will work.
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