Flash development for linux in general has been ceased by Adobe.
There are lots of alternatives.
Download Firefox from the App Store, and use that, it has a new open source flash substitute that works just fine and that will allow whatever flash games to run, and it will be a hell of a lot safer than using Adobe Flash.
Actually, it's just badly written Flash things that need to die but since there'll always be morons writing those, next best thing is just to have the whole thing die, or said writers.