StarTropics (1990) is the one where Nintendo broke the fourth wall and reached into your physical world. You play Mike Jones, searching tropical islands for your kidnapped uncle, fighting with a yo-yo in a Zelda-style top-down adventure.

Its legend is one puzzle: the game tells you to dip a letter in water for a code. Players were baffled — until they remembered the game shipped with an actual physical letter, and dipping it in water revealed the number. No internet, no FAQ; just you and a wet piece of paper.

A charming, weird, very Western-feeling Nintendo game. That letter trick is one of gaming's greatest packaging gags.