Developer Hopoo Games has announced Risk of Rain 2 has topped 650,000 players.

The new milestone was reached within the first week of the game hitting Windows PC, via Steam Early Access. Within that number is 150,000 people who brought in another friend via the “Buy One Get One” launch deal.

“I just wanted to say from the whole team how absolutely floored we are with the reception so far,” Hopoo Games co-founder Duncan Drummond said in a blog update. “I was personally hoping for something to match at least half of the original game: apparently we’re doing a LOT better. It’s absolutely surreal – thank you all again.”

The first post-early access update was was released for the game on April 3rd, addressing the initial community feedback. The plan moving forward is to add more content like characters, levels, bosses, and items, as well as making sure the game is really polished for its eventual full release.