Part 1
—"No worries": common Australian term, "don't worry about it." Shows a feeling of friendship.
—The name Monopoly refers to the economic term, which describes when a single person or company controls a commodity, not the board game.
—Note that the Golden Oaks library is still intact in this story. This takes place during Season 4, before the finale.

Part 2
—Witnesses disappearing: I think we all know what that implies.
—Phillip's crime sense is explained here. What is not explained is a rather important point: Phillip's crime sense only goes off when he needs to intervene.
—Phillip shivering when he gets a crime sense warning only happens when somepony he cares about is in danger. The greater the danger, the more he shivers.

Part 4
—Rainbow Dash attempts the old "How did you know something specific that I didn't tell you" trap on Monopoly, but it doesn't work.

Part 5
—Like Sherlock Holmes, Phillip has a well-stocked personal laboratory in his home, where he performs experiments, research and analyzes evidence.
—Same brand I used to smoke: Phillip used to smoke, but quit before he came to Ponyville. This is another reference to Sherlock Holmes, who was known for his drug use.
—Again, Phillip shivers, signaling that friend is in danger.
—In the original text, the intruder would reach for his pants, implying that he intended to rape Fluttershy. I cut this as it was too obscene.
—I gave Phillip a boomerang as a long-range weapon, deciding that he is not the kind to use a gun and that a bow and arrows would be too large for him to carry. It is a reference to both his Australian heritage and Batman.
—"Not in my town": notice the phrasing here. Phillip sees himself as a defender of the town and it's citizens.