According to the Steam page, this game does not support Intel Integrated graphics. I don't understand why that is when a majority, if not all of the Mac machines sold to consumers use Intel Integrated graphics. Am I missing something? Did they develop this game for 4 or 5 year old Mac's that have dedicated graphics cards?

Integrated graphics cards are poop. They're better than they were, sure, and you can get some respectable gaming done on them, but they're still not good. Cities Skylines is probably a CPU intensive game anyway and they probably didn't want to try to support something that would take away a chunk of processing power.

Or they are just supporting the Pro lines of Apple products, which I believe all have dedicated graphics cards.

As believer said, Integrated cards really are poop. They have come a long way, but they just aren't made for running modern games.

@coreymw: It actually does work on my 2014 Pro Retina with Intel Iris Pro graphics. I put everything on medium at 1280x800 or something and it wasn't playable. I didn't even bother with low, maybe it could hit 30 FPS with everything turned all the way down though. As an aside, Steam In-Home Streaming with Cities doesn't work very well at all. I couldn't get my middle mouse button to work either using the mouse attached to the host machine or the client, and rebinding the free camera key to other mouse keys or a keyboard key doesn't work. Maybe that will get fixed with an update, but for now I'm strictly playing on PC. On the upside, Steam Cloud Saves are cross-platform and do work, so you can start a game on your Mac and pick it up later on PC, or vice-versa.

@ssully Mac Pro desktops have GPUs, or at least can have them. In Macbook Pros, discrete cards are an option but most use Intel integrated graphics, which aren't even cards. They are part of the CPU.

@coreymw When they say it isn't supported, they just mean it hasn't been tested. However, it should work, even if badly. It is an integrated card and the OSX OpenGL driver isn't very performant so don't expect any miracles. A better bet is that you should try it in bootcamp, but you're still dealing with integrated graphics and the intel dx driver isn't that optimized for games.

After doing more research it appears that anything with an hd4000 or later will work, but you're going to have a bad time.

Thanks for the replies.