"[5 Turns] Grants immunity to Ice, +25% ATK and attacks gain Ice attribute. Removes Flaming Aura."
Cost: 5 MP
Source: Equipping the Shadow Core.
Chilling Aura is a spell that applies a buff that makes the user's default attacks and grants immunity to the 
Ice element along with +25% ATK (Not the same as a standard STAT Up) for five turns to the user. It will also remove the buff granted by Flaming Aura if it is active.
This skill is best used in prolonged fights by a physical attacker such as Veronica (or anyone else with an ATK build) to buff their primary means of doing damage, as well as giving a more accessible means of dealing Ice damage as Veronica's spells are hampered by her low MAT. However, it can be used solely for the immunity to Ice, should you need it.