Ah, Dead Island. The zombie-shooter set on a lucious resort island was a success, with Guido Eickmeyer, development director and executive producer of games at publisher, Deep Silver, attributing the game's success to the inclusion of cooperative gameplay.

Considering Dead Island sold 4 million copies, on an investment of less than $25 million, it is not bad at all. Especially with AAA titles receiving hundred-plus million dollar budgets these days, Eickmeyer is quoted as saying:

This is why we got all the good reviews from users. This is why we got high user ratings, because it is the most exciting co-op experience that is on the market.

Dead Island has some great co-op stats, too, with over 56 million hours played in co-op, which mounts up to an incredible 6,500 years total. Dead Island: Riptide was announced at Gamescom this week, and will be another "huge co-op experience".