In all honesty, I'm not at all a programmer or game designer.
However, I can point you to a few options and you can choose from there.
I have a few game engines listed on [url="http://www.linuxgameconsortium.com/game-development"]Linux Game Consortium[/url].
[url="http://www.linuxgamenews.com/post/23114389500/open-source-platforms-for-mobile-apps-and-games"]Linux Game News[/url] has a few other choices, commerial options we've come across.
[url="http://www.linuxgamenews.com/post/25385115766/unity-4-pre-orders-microtransaction-asset-store"]Unity[/url] is also another option for cross-platform gaming.
Linux Game News &
Linux Game Consortium