Fortnite
via Epic Games

The massive popularity of co-op survival game Fortnite is making Epic Games a lot of money.

The game developers recently made the game against in Apple’s App Store and its shot right to the top.

Though the game is still only available on an invite-only basis, it has reportedly made $1.5 million in in-app purchased in just four days. In the first three days, the game earned $1 million USD.

While in-app purchases aren’t surprising, it’s surprising Epic is making so much money while Fortnite is still invite-only.

Fortnite has been popular among XBOX Live and PlayStation Live for some time, but recently, news of Drake and Travis Scott playing with Twitch streamer Ninja made a lot more casual gamers take notice.