This is going to be painful but not as bad as Debbie's. You do need to end chapters to get the medals, right(sigh)...? So to get the most medals (3), you'll need a straight run through either Leon or Jake's Chapter 4.
Since you can pick a chapter part-way through I'll just do Chris 3-5 or Jake 4-5, get the medal and become a participant. Let people hack their highscores so that the overall goal is met.
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