The Gokaigers were literally searching for treasure.

But their Ranger Keys effectively turned the history of Super Sentai into another kind of treasure.

Every key represented a previous team.

Every legendary Ranger appearance represented another piece of the franchise’s history.

The idea was clever because it allowed the anniversary concept to become part of the story rather than simply appearing as nostalgia.

Super Sentai’s past was literally something the characters could carry with them.