Basic Information
Conjuration (from the Latin literally "swearing together") used to refer primarily to the practice of calling up supernatural entities and bargaining with them - the sort of thing more normally classified as summon magic or invocation in the modern era.
These days - and largely due to the connotations of making something appear out of nowhere - conjuration tends to refer to workings that bring physical objects or creatures from one place to another (or create them out of thin air, although this might also be called evocation). See also apportation - a (sub)school of magic specifically concerned with moving things from place to place.
In some systems, this will still be considered an aspect of summon magic or invocation.
There is likely to be a sliding scale of difficulty and power requirement - moving things from one place to the other is likely to be comparatively trivial compared to creating them from scratch. Even than, creating a temporary object from ectoplasm and giving it enough form to be useful is likely to be easier than pulling one together from its component atoms or the sort of mass-energy conversion that would be required to make one literally from nothing. Bending reality out of shape to create a temporary object that has no existence before or after hand may or may not be easier. Many settings make things created by conjuration fade away over time - if so, the best explanations are likely to be ectoplasm (which sublimes back into the otherworld if not closely supervised) or being pulled from another reality and drifting back there unless held in place.
Also, any kind of conjuration/creation magic is liable to challenge the user's craft skills - if you don't know the working parts of a handgun intimately and have no idea what they are meant to be made of or what stresses they need to contain, you may get a solid, pistol shaped object, a dangerous piece of junk that explodes on firing or anything in between. Conversely, trying to summon an object you are not clear about may also get you some odd results (again, the handgun example might snatch a pistol shaped cigarette lighter, a waterpistol, a deactivated relic or a random design of pistol … with or without ammunition … from almost any point in history, even if the user is really emphatic that they want a M45 MEU(SOC), olive drab finish and a full magazine.).
Sources
Game and Story Use
- Different types of conjuration will have a very different feel - one that calls a known object to you will be very different to one that snatches a random example from somewhere in the multiverse (especially if it doesn't return it afterwards…), as will the sort that creates the item to spec (and see above for how well that might turn out).
- Conjuration failures may be a popular source of humour … even of the gallows variety…
- Combine the two - if the PCs wizards are struggling to summon a usable sword, emphasise an opponent's power level by having them pull a working Uzi out of thin air and start laying down lead.
- A conjurer might be perceptive and curious if creating objects requires knowing their inner workings, lazy if conjuration grabs a random example from elsewhere, or greedy if some kind of metaphysical ownership is needed to summon something.
- Bending reality out of shape may be a really scary way of doing this … and when they are destroyed it may be possible to use the energy of reality snapping back for something as well. For an excellent treatment of this see Tad Williams' Memory, Sorrow and Thorn books.