The game was an instant, monster-size hit that spawned a multibillion-dollar empire of movies, TV shows, theme parks, and, of course, trading cards. When it reached the U.S. in 1999, kids across ...

Overall value of the cards has spiked by 20% in the past six months—according ... monster-size hit that spawned a multibillion-dollar empire of movies, TV shows, theme parks, and, of course ...