Just parkour. Up the side of a mountain. I suppose this one also gets you thinking a little bit, as you need to investigate your surroundings a little to see where you need to jump next. Basically, just play on peaceful, don't break blocks you didn't place, only place torches and ladders you get from chests, and start at the sign that you're told to.
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FINE. HERE'S A PICTURE FOR YOU.
Isn't it amazing.