Regular 
Raises the temperature of an object. It does not necessarily produce fire, though most things will burn if heated enough. Heat will be radiated away normally. (Use this as a guideline for playable effects – don’t try to turn the spell into a physics exercise!) 
Any wizard planning to make extensive use of this spell should arm himself with a list of the melting points of various materials. The spell can have drawbacks. If you were in jail, you might melt your way through the bars . . . but the radiated heat would probably broil you first.

Duration: 1 minute. Each minute raises the target’s temperature by 20°. Maximum temperature possible with this spell is 2,800°. 
Cost: 1 for an object up to the size of a fist, 2 for an object up to one cubic yard, and 2 per cubic yard for a larger object. Temperature change can be doubled to 40° per minute for double cost, tripled to 60° per minute for triple cost, and so on. Slower heating costs no less. Same cost to maintain. 
Time to cast: 1 minute. 
Prerequisites: Create Fire and Shape Fire.

Item 
Staff, wand, or jewelry.  
Energy cost to create: 400; item must include a ruby worth $300.