The round, announced Wednesday, also includes funding from previous investors Union Square Ventures, Foundry Group, and Avalon Ventures.
Zynga, based in San Francisco and started by Tribe.net social-network founder Mark Pincus, added that Bing Gordon, a Kleiner Perkins partner and former chief creative officer of Electronic Arts, is joining Zynga's board. Zynga also announced its acquisition of YoVille, which it describes as the "largest virtual world game on social networks."
The start-up announced an initial funding round of $10 million in January with investors including LinkedIn Chairman Reid Hoffman and PayPal co-founder Peter Thiel.
Zynga's social games include a poker match that lets players send virtual drinks to friends. According to its site, Zynga also offers other casino games, word games, role-playing, and board games.
The service, which boasts 18 million monthly visitors, makes money through ads and selling customers add-ons to the games."