What is the difference between regular lager beer and Ice varieties of beer?

Generally Ice beer refers to a beer that has been strengthened by freezing some of the water out, concentrating the remainder. A lot of Canadian breweries have been doing this for a long time, and in Germany it's often done to bock beers, making a style called eisbock. more detail: Ethanol, the alcohol that you drink in beer, freezes at a very low temperature compared to water. So if you take a beer, lower it to below 32 degrees f, and remove the solid ice that forms, what remains will be more alcoholic than what you started with.