How to get the Mystery Achievement [MCC]

Before we begin you need at least one of any of the halo games, i personally did it on Halo: 3 but any other game should work, anyways without further ado. Let's begin

Head to multiplayer and then Custom multiplayer.

There you should see a couple games, click on any one of them. Now that you are in the Custom game settings, you should see File options.

Click on save as. THIS IS THE IMPORTANT PART!. Type ".fortune"

And Done! That's all to get the Mystery Achievement.

Thank you for reading this guide! Hope you have a nice day and enjoy your new achievement.

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