グラスホッパー・マニファクチュア
On December 2, 2009, it was announced that Yamaoka was leaving his long term employer Konami. On February 3, 2010, it was announced that Yamaoka has joined Grasshopper Manufacture and was working with Goichi Suda and Shinji Mikami on their action game, "Shadows of the Damned". He was first appointed to the role of chief sound officer at Grasshopper, but became involved in aspects of game production as well.