Dresden Files: New York
Thaumaturgy is a subtle art—and slow. It was created by mortal spellcasters due to their need to produce great power but to keep that power under control better than Evocation ever could. This is done through careful preparation and ritual: Thaumatury can’t ever be used quickly enough to be much use in a fight. However, given enough time, preparation, materials, and the right caster, it’s more than a match for supernatural forces.
You’re able to use Thaumaturgy in all of its forms, as described on page 261.
Full Thaumaturgy grants the ability to specialize in one form of thaumaturgical magic, usually by focusing on a particular application (such as ectomancy, crafting, or divination—see page 272). This specialization can take one of two forms—either a complexity bonus, increasing the level of complexity you can manage without preparation by one for spells of a particular type, or a control bonus, increasing your rolls to control the specified ritual by one (crafting uses different bonus types—see page 280). One or the other must be chosen, though the specialization does not need to be defined at the time the ability is taken. Additional specializations covering different areas of Thaumaturgy may be taken by use of the Refinement ability.
Thaumaturgy comes with two free Focus Item Slots. You can design the items that fit into these slots now, or later on during play. A single Focus Item Slot may be traded in for two Enchanted Item Slots. You may gain more Item Slots as one of the options on the Refinement ability.