The San Francisco-based game company said it expects to cut 314 jobs as part of an expanded cost savings plan. Zynga also posted a narrower-than expected quarterly loss, and its shares soared to $4.26 after closing at $3.56 on the Nasdaq.

Zynga said it acquired NaturalMotion, which has created games like "Clumsy Ninja" for Apple mobile devices, for $527 million in cash and stock in a bid to grow its mobile game revenue.

"The missive is kind of the framework of a turnaround," Mike Hickey, an analyst at the Benchmark Company, said.

In July, Zynga hired the former head of Microsoft Corp's Xbox business, Don Mattrick, to replace co-founder Mark Pincus as CEO. Mattrick has been managing a series of layoffs, cutting costs and reviewing the company's product pipeline.

While the management's recent steps show a "a ray of optimism," key metrics of user engagement were still weak and Zynga must prove that it can use NaturalMotion's games and talent to deliver titles that are long-lasting hits in a fad-driven mobile game market, Hickey said.

"Look at Draw Something....that was something that on the surface looked great but quickly evaporated," Hickey said.

Zynga had scant success with its 2012 acquisition of OMGPOP, the New York-based studio that created "Draw Something," for about $200 million.

Zynga's core business continued to deteriorate, but not as quickly Wall Street feared. For the quarter ended Dec 31, Zynga's revenue fell to $176.4 million from $311.16 million a year prior, compared to analysts' average estimate of $141.1 million, according to Thomson Reuters I/B/E/S.

Excluding certain items, it reported a net loss per share of 3 cents, slightly better than Wall Street view of a 4-cent loss per share, according to Thomson Reuters I/B/E/S.

The company forecast first-quarter revenue in the range of $155 million to $165 million, surpassing Wall Street's estimates of $145.6 million, according to Thomson Reuters I/B/E/S.

The game publisher, once among the hottest tech companies with rapid revenue growth from popular Facebook-based games, was caught off guard as the games industry saw a boom in mobile games. The company has renewed its focus on transitioning to smartphones and tablet titles, the increasingly preferred format for casual gamers.

"The guidance for 2014 was strong, even exiting out the deal, it was in excess of what the Street was looking for and that shows the stabilization and expected re-growth of their business," Hickey said.

(Reporting by Malathi Nayak; Editing by Andre Grenon, Nick Zieminski and Meredith Mazzilli)

By Malathi Nayak and Gerry Shih