Old Mastery reverted this added:
Mastery: Frostburn When you damage enemies with Frostbolt, Frostfire Bolt, and your Water Elemental's Waterbolt, 12% of the damage done is stored as an Icicle with you, for 15 sec. Up to 5 Icicles can be stored at once. Casting Ice Lance causes any Icicles to begin launching at the target. Mage - Frost Spec.
Ice lance damage buff to compensate for old mastery removed.