-You ride FearFall at Kentucky Kingdom (or any other Larson drop tower) and you can deduce exactly when it's going to drop without needing to sit on the side that casts a shadow.
-The majority of your Steam activity consists of either posting NL2 screenshots or NL2 workshop items.
-Your favorite levels in Super Mario World are Roy's Castle and Larry's Castle just because of the brown platform that moves like a roller coaster.
-You're 30 years old and still play with one of these: