Flash doesn't include any type of information that can tell to the robots about the type of the element or the type of info is available on the website. There fore if the Google Crawler cannot access that info it will consider it by default an "element outside of the webmaster tools". That is why most of the webmasters recommend on NOT using a flash website or a flash component. It also makes it in the eye of the crawler an "advertising element".
I think flash affects the load time of your website. Google credits sites that load faster and may penalize your site if it loads slowly all the time. So this way it affects your ranking. Hope this helps
flash cant send user on site, u have to write unique content for ur games description also choose keywords wisely to get good result in coming days.