Of course there´s a chocolate egg involved - well, actually an easter egg, but they are usually made of chocolate. The idea is that you send a person the gække letter anonymously and then they are supposed to guess the sender before Easter. If they guess correctly, the sender has to give them an easter egg, if they don´t they have to give one to the sender. Which is why it is not particularly fun if people are expecting a letter from you, see?
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