As above, the Intel integrated graphics are lousy for gaming. They're much better than previous generations, and will now actually handle older games at basic settings, but they're hopeless for decent framerates on intensive games at even moderate settings.
Whether your laptop is a Macbook or Toshiba or whatever, it's going to have the exact same problem trying to run games on integrated graphics. Ultimately, this was a total failure of research - you didn't know what you were buying and bought something that didn't meet your needs.
For even modest gaming, you want a discrete graphics card. For the games you're talking about (Far Cry), you want a fairly solid and capable discrete graphics card - the 650M that's in the 15" Retina MBP or better.
I've been waiting several months with cash burning a hole in my wallet for the eventual upgrade to the 15" Retina MBP *specifically* for an upgraded discrete video card, as the 650M is solid, but I'd really like the current generation of discrete card.
The unfortunate reality is that you're going to have a rough time finding what you want. General-use laptops in a reasonable price range just really aren't good gaming rigs. Running even a mid-range discreet graphics card hard in a laptop case uses a ton of power and creates a lot of heat. Dedicated gaming laptops like Alienware handle this with somewhat expensive, massive heavy cases, loud fans, etc, and Razer is trying it with very expensive laptops ($2K min) that are thin and light with great graphics cards, but there's a reason nobody is selling $1K gaming laptops that kick ass, and are pleasant and portable...
In a lot of ways, the 'sane' way to go about this is to buy an MBA and a fairly modest PC gaming rig, like an Alienware X51 - not especially cheap, but far cheaper than trying to get thin/light gaming laptop.
Long story short - integrated graphics suck, good gaming laptops are expensive and/or heavy and large, get an MBA and an X51, and then you'll have what you probably really wanted all along.