Video game publisher Activision Blizzard‘s shares leaped Friday after unexpectedly strong fourth quarter results and a share buyback announcement.

The Santa Monica, California-based company reported adjusted earnings of 92 cents a share for the fourth quarter, 19 cents above estimates, while revenue of $2.45 billion also topped expectations. The company said it had 447 million monthly active users in the quarter, including a record number of monthly active users in the Blizzard division.

Activision Blizzard attributed the solid results to its successful multiplayer shooter game “Overwatch” and its acquisition of “Candy Crush” maker King Digital last year. The company is known for blockbuster franchises like “Call of Duty” and “World of Warcraft.”

The firm also announced a two-year buyback program of $1 billion in outstanding common stock, beginning Feb. 13, 2017.

Shares gained more than 18 percent in Friday trade. With Friday’s gains, the stock has surged 30 percent so far this year.