Don't use a Mac for gaming.
But my Mac's SuperDrive is filled with dust and won't read it. I have two serial numbers (the first copy I bought was broken) but I can't use my disc drive. How should I go about this in a way that's legal as long as I have a serial number?
I'm sorry I didn't have a half-decent PC at the time of the game's purchase, Mayor McHelpful.
did you try taking it out and replacing it with another one
Get it for a console then. Its only like 15 bucks.
The disc was broken? And this is a MacBook Pro?
You may have tried it already, but buy some of the compressed air in a can and spray out the disc drive as good as possible.
check the web for (uncracked and therefore legal) downloads of the game, also check out the company's website and maybe email support.
Take care of your superdrive better next time.