Candy Crush Saga maker King Digital Entertainment PLC has acquired Seattle-based mobile game studio Z2Live Inc. (Z2) for $150 million, consisting of $45 million in cash up front, and up to $105 million of additional cash linked to future events.

Founded in 2009, Z2 currently offers two titles: Metalstorm Online and the fairly popular game Battle Nations. The latter title is the key earner for Z2, with 500,000-1 million downloads on Android, and significantly more on Apple’s App Store; although offered for free, like all good freemium games it hooks people in on the free side, then entices them to buy add-ons, some of which can cost up to $99.99.

“Through this acquisition, the company will incorporate a proven team focused on contributing to our diversification into new genres,” King said in a statement, while noting that the deal will give King its first studio in the United States.

Z2 had raised $6.5 million over three rounds prior to acquisition from investors including Madrona Venture Group and Draper Fisher Jurvetson.

The news of the acquisition broke as part of King’s Q4 and year ending December 31st financials release.

The company reported 1.5 billion average game plays during the fourth quarter, with gross bookings of $2.4 billion in 2014. King reported $661 million in net cash generation in 2014 and ended the year with $964 million cash and cash equivalents

Executives said in a conference call reported by GeekWire that the Z2 acquisition will help expand their gaming franchise’s lineup outside of the casual gaming genre. CEO Riccardo Zacconi added that Z2 was a “great cultural fit,” and that they look “forward to welcoming them to King and joining forces to push this opportunity together.”

Founded in 2003, King.com is best known for its mega hit Candy Crush Saga. After raising $43 million from Index Ventures and Apax Partners in 2005, the company floated on the New York Stock Exchange in March 2014 (NYSE:KING)

The market liked the news of the acquisition of Z2 and the strong revenue figures for 2014, with the stock up 4.24 percent in after hours trading to $14.74, giving King a market cap of $4.51 billion.