Perfect Illusion

Area 
As Complex Illusion, but affects all the senses except touch; your hand will go through it. It cannot be dispelled except by Dispel Magic or Dispel Illusion. Any damage at all will temporarily disturb the illusion, revealing it for what it is without  dispelling it.

Duration: 1 minute. 
Base cost: 3 to cast. Half that to maintain. For double cost, even the sense of touch will be fooled, though you cannot “really” warm yourself from an illusionary fire. 
Prerequisites: Magery 1 and Complex Illusion.