FrWOLF Winter Wolf
Frost wolves are found together in large packs, and with Frost Giants. They're mostly found in the Ice Cave, but also on the overworld toward the end of the game, and the last dungeon.
Fighting frost wolves can be good for getting G and experience, but they can be dangerous. The only problem with them is their Frost attack, which can take an unprepared party down easily. Fortunately, one shot of Fir2 can take a whole pack out at once, and Fir3 definately will.
Frost Wolves are called Winter Wolves in the Japanese version and FF Origins. Winter wolves come from Dungeons & Dragons. They are large, intelligent wolves who live in cold climates and can breathe frost from their lungs. You won't find them in later FF games, but for more wolfy goodness, see the Wolf page.