In a bid to expand into the mobile gaming industry, Activision Blizzard Inc. intends to acquire mobile game developer King Digital Entertainment for $5.9 billion.

The purchase is being paid for with $3.6 billion in cash and a $2.3 billion loan. The deal has been unanimously approved by both companies’ boards and is expected to close by spring 2016.

King Digital of Dublin, Ireland makes the widely popular mobile puzzle games Candy Crush and Farm Heroes, as well as a number of lesser-known mobile games.

Santa Monica’s Activision makes a number of popular PC and console games, such as Call of Duty and World of Warcraft, but few mobile games. Activision said the King Digital acquisition would help the company gain access to the faster-growing mobile-gaming industry.

During the last 12 months ending Sept. 30, Activision had non-GAAP revenue of $4.7 billion and King had adjusted revenue of $2.1 billion. Activision Blizzard had a GAAP net income of $1.1 billion and King had IFRS profit of $600 million.

Activision’s bet may be dicey, however, as King’s recently slumping revenue has driven its market valuation down 31 percent since its initial public offering in 2014. A large portion of King Digital’s revenue comes from Candy Crush, which can still be classified as a megahit game but has perhaps peaked in popularity. The game has seen shrinking revenue, which comes from in-game purchases such as extra lives. Mobile-game hits of that size are also notoriously hard to repeat.

Activision might be able to milk Candy Crush’s remaining revenue, then use King Digital’s mobile-game expertise to launch new titles, said Andrew Stalbow, chief executive of Venice mobile-game developer Seriously.

“Ultimately, I think Activision will use Candy Crush as a revenue stream, build out the franchise into something bigger and use the platform to promote their next round of games,” he said.

What’s more, said Stalbow, Activision’s purchase might spur increased activity in the gaming industry.

“Activision’s purchase of King will lead to a lot of their competitors wanting to be similarly aggressive, whether building organically or through acquisitions,” he said.

Activision’s share price climbed from $32.50 a share at close of Monday to $35.82 a share at close today following the announcement. The deal won’t become final until it’s approved by King’s shareholders and government authorities, among other conditions.

Technology reporter Garrett Reim can be reached at [email protected]. Follow him on Twitter @garrettreim for the latest in L.A. tech news.