An alien wearing a top hat is seen standing in front of what he himself aptly named, the “Memory Evaluation” tunnel. You were a playtester, being invited to try it out. Said alien faces towards you, and clears his throat.
“Ladies and gentlemen, welcome to the Grand Opening of the Memory Evaluation!” He began. “Unlike any tunnel you've yet seen, the tunnel before you was designed by an expert! Each trial is a challenge to your recollection. Will you be able to pass all seven?” The extraterrestrial then shifts his gaze leftward, gesturing to the majority of the passageway. “In the former half of each trial, you are granted the opportunity to study the pattern of obstacles. The latter half then plunges you into darkness. Good luck!” Pausing for a moment. “Before you begin, please be advised that the colorful tetrahedral decorations are the property of the Gentleman.” That must have been his name... “Should you collect any, return them to me before exiting the attraction. Now, without further ado... Please enjoy your journey!”