Cryogonal has decent speed and SpAtk and high SpDef but has horrible defense and attack. One physical fire or rock move could probably OHKO it.
Vanilluxe has decent defense, HP, attack, SpDef and high SpAtk, but he is a bit slow.
I think i'd go with Cryogonal.
Item: Focus Sash (may save you from any physical fire or rock type move)
Nature: Modest (+ SpAtk, - Atk)
Blizzard - STAB, 100% acc. due to hail.
Hail - Makes blizzard 100% acc.
Flash Cannon - Covers rock types, may lower opponent's SpDef.
Acid Armor - Get rid of that horrible defense.