HONG KONG — For North Korea experts, virtually every detail in the authoritarian state is a potential window into the political priorities of its elusive leader, Kim Jong-un.

A mass gymnastics performance that ended in North Korea on Sunday, after a nearly two-month run, was no exception: Unlike in previous years, this year’s edition was said to highlight recent changes in Mr. Kim’s posture toward China, South Korea and the United States.

Jump Around Dept.: What Are the Mass Games?

This year’s Mass Games gymnastics bonanza, which began in early September in the capital, Pyongyang, was the first edition of the event since 2013. Along with a military parade in September, it marked the 70th anniversary of the founding of North Korea.

The performance, “Glorious Country,” featured about 17,000 schoolchildren who formed a “human-pixel” backdrop with colored cards in the stands, plus thousands of performers on the arena’s floor, according to Andray Abrahamian, a fellow at Stanford University and the author of a book on North Korea who attended the show in September.