Dead Island 2 has only been out for three days, and has already hit 1 million copies. 

Developer Dambuster Studios confirmed the news, saying its first-person zombie game had a "mind-blowing launch" after its April 21 release. That's pretty good on its own, but even more impressive considering how long Dead Island 2 has been in development. 

The third game in the zombie-killing series was first announced in 2014 for a release the following year. Since then, it's changed hands from Spec Ops: The Line's Yager Development to Crackdown 3's Sumo Digital, then finally to Dambuster in 2019. 

Incidentally, this also marks the UK-based studio's third game entirely, preceded by 2016's Homefront: The Revolution (as a restructured Crytek UK) and 2021's Chorus. 

Along with the sales milestone, Dambuster revealed some fun in-game statistics. To date, players have spent 11 million hours in Dead Island 2. In that time, the game has seen 28 million player deaths, 45 million zombies get sliced in half, and 1.1 billion total undead have been made dead again on the island of LA (or Hell-A, as it's known in-game). 

How did Dead Island 2 sell so many copies? 

Video games are often a crap shoot when it comes to success, and there's no real way to figure out what'll succeed and what won't. In the case of Dead Island 2, it's even more interesting when you take into account its development period and how it jumped up a week to get out of the way of April 28's Star Wars Jedi: Survivor. 

2011's Dead Island (from Dying Light studio Techland) took off extremely well, and the fondness for that game arguably played a big part in the sequel's sales boom. There's plenty of games where one can kill zombies (especially with friends), but the series appears to have something that's resonated with players even a decade later. 

In that way, the Dead Island series isn't that far removed from the Dying Light franchise. Techland's zombie parkour series hit it off pretty big with that first game from 2015, and 2022's Dying Light 2 Stay Human reached 5 million sales within its first month of release. 

The apparent lesson may just be that killing zombies never loses its appeal with audiences, particularly if it can be done in a memorable, first-person way.