That’s because Diablo III, Blizzard Entertainment’s first new installment of the dark fantasy franchise in 12 years, is finally being released on May 15. If you’ve played Diablo (1996) or Diablo II (2000), you already know why this is a landmark event. Those videogames not only elevated the dungeon-crawl aesthetic to biblically-tinged high art, they paved the way for mythologically-resonant, story-driven RPGs from Star Wars: Knights of the Old Republic to Mass Effect. But if you haven’t ever immersed yourself in the world of Diablo before, consider this: at the time of its release in 2000, Diablo II was the fastest-selling computer game ever made. Though that record has since been eclipsed (Hello, World of Warcraft!), both entries of the franchise together have sold nearly 20 million copies worldwide.