Deca Games has acquired Zombie Catchers, a hit mobile game with more than 55 million downloads, in a bid to reinvigorate the indie title.

The Berlin-based Deca Games has expertise in live operations, and it rescues older mobile games and tries to get them growing again. It has acquired Zombie Catchers from Helsinki-based studio Two Men and a Dog.

Deca Games was started in 2016 by CEO Ken Go and other former veterans of mobile game publisher Kabam, which Netmarble acquired. Similar to rival RockYou, Deca’s strategy is to take over aging games, invest in updates for fans, and operate them profitably.

“We are 100 percent focused on live operations, and this is a case where players couldn’t get enough of the game,” Go said in an interview with GamesBeat. “Players hit the end of the single-player game and they keep playing. That’s super rare.”

With Zombie Catchers, Deca now has six games in its portfolio.

Go said Deca will continue the game’s development and plans to release new content and expansions for the game’s existing fans, as well as continue to grow the game’s audience. Zombie Catchers debuted four years ago, but the small team of two that made it hasn’t been able to update it much.

“After the successful run of Zombie Catchers, we wanted to shift our focus to creating new games, however our fans were craving further expansions,” said Matti Kallonen, CEO of Two Men and a Dog, in a statement. “We talked with Deca and immediately saw that they would be an ideal partner to take the game forward. With Deca, we have no doubt that Zombie Catchers will continue successfully for another decade.”

Kallonen and his cofounder Aleksi Raisanen are focused on making a new game. Deca has more than 50 people in Berlin, San Francisco, and Eastern Europe.

Zombie Catchers still gets two million downloads a month and it has about a million daily active users. Deca, which also operates the eight-year-old Realm of the Mad God, will likely take the game to new mobile platforms.