You have to see my setup to understand the reasoning behind this nutzoid set.
but its basically someone has SD-and then for sheer novelty-pass to Glaceon. Everyone thinks its a mistake pass, they get ready to murder poor Glaceon-and then Ice Shard rapes the sucker. Out comes their Starmie/whatever to try and end me, I know I can survive it (Haha Focus Sash)-Ice Beam or Shadowball it, then merc it with Ice Shard. They try to put me to sleep-I still attack, mwahaha. It takes crazy prediction.
Back on track here....Another ok set for Glaceon would be the classic Hail set.
Hail
Blizzard
Shadowball
Double Team/Natural Gift
That's if DT is allowed...but anyway. Simple enough. Hail causes your evasion to rise, Blizzard hits 100%-w STAB, its gonna hurt alot of things that don't outright 2x resist it. Double Team to confuzzle them even more, and SB for bothersome Ghosts and Psychics. Natural gift is always an option too :O.
Granted, I don't know the setup of your team, and Hail may be a hinderance more than a help.