Dying Light is developer Techland's most recent release. The game has apparently sold extremely well, as the number of users has recently been clocked at over three million. This number doesn't mean that the players are in Dying Light at the same time, otherwise this feat would be even more astounding.
That said, with three million players using your game at different times of the day, you're still going to see some pretty big statistics. Techland has published this infographic, which shows how far the community has traveled, how many zombies they've killed and more:
The Night Hunter just became even more terrifying, folks. The fact that it's player-controlled definitely makes it more dangerous, but it's not very often you see evil factions triumph over good.