Sega, the Japanese gaming company known for popular franchises such as Sonic the Hedgehog and Total War, has made a 706 million euro ($776 million) offer to acquire Finland’s Rovio Entertainment Oyj, the maker of the popular Angry Birds puzzle game.

According to Sega, the deal would be for the entirety of Rovio’s outstanding shares and options, valuing the stocks at 9.25 euros per share, a 19% premium to their closing price before the announcement. Rovio’s board has also expressed support for the offer.

Rovio games have been downloaded more than 5 billion times, with the Angry Birds franchise having been licensed into other entertainment and consumer products. Sega aims to expand its presence in the mobile gaming market by using Rovio's live-operated mobile game development capabilities to boost mobile-based versions of its existing games.

Sega Sammy, the holding company of Sega following its merger with games maker Sammy in 2004, saw a 4.2% decline in its shares before the acquisition was announced. Rovio shares were up 17.88% at 9 a.m. London time.