Keystone Ice is the so-called "ice beer" version of Keystone Light (or just plain Keystone), which is purportedly "regular" beer which has been subjected to "ice brewing"—that is, lowering the temperature to below freezing so that water freezes out, yielding higher levels of alcohol.
(Of course, the actual process may be quite different, but that’s the traditional
urban legend story and I’m too lazy to look it up right now.)
Keystone Ice, brewed in fact by Coors, is 5.9% alcohol by volume—fairly strong if you’re used to drinking ~4.5% beers—and comes in a "specially lined can".
Appearance: Deeper golden color than is typical or expected for the Macro category. White fizzy head fell flat pretty quick.
Smell: Really clean and neutral aroma; a bit of hard water, a bit of a soapy note that you get sometimes from the carbonation.
Taste: Corn, sweet enough so that it’s almost cloying; that’s the predominant flavor here and it’s hard to get past it. Otherwise, fairly non-descript.
Mouthfeel: A bit more body than a typical Macro. Fairly smooth, but leaves an odd coating/residue in the mouth.
Overall: More body seems more appealing than a typical Macro, but the excessively sweet corn is off-putting and screams "cheap".