Literally "calling forth"1, Evocation is the school of magic most associated with flashy, overt effects. When a wizard throws fire or lightning about or summons up gusts of wind, that is typically what is meant by evocation and such things may well extend to bolts of pure magical energy or kinetic force. Depending on how magic functions in the setting, this may or may not be considered a direct attack for purposes of magical resistance - some systems consider magical fire to be resisted the same as any other magic, others that it is resisted the same as any other fire … the two concepts are rarely compatible.
To be useful, evocation would seem to require a short casting time - a fireball called up by an hour long ritual is going to be of very limited use unless it includes some awesome homing capabilities or is fired at a very predictable target. That doesn't necessarily mean that an all ritual magic setting can't use these effects - it's just that they will need more preparation. For example, to shoot lightning a caster might need to call up a storm, ritually attune himself to it and then call it down from the clouds2, probably by pointing with his wand. Alternatively the caster might attach a charm of some kind to the target and then use that as a homing beacon for his attack - other uses of the laws of magic are entirely probable.
Game and Story Use
- Compare, for example, the Dresdenverse where magic is divided between evocation - instant, messy, mostly about blasting things - and thaumaturgy - the slower, ritual end of magic that does all the fine work.
- Note that, as stated above, evocation may well poach on the estates of elemental magic.
- Expect a specialist evoker to be proactive, possibly even aggressive, but certainly confident and likely to be "quick on the draw" - if you specialise in putting attacks down range, being first up is likely to matter.
- An evoker playing against type might be cautious, respectful of magic's destructive power and unwilling to make final decisions hastily.
- Expect gunslinger tropes to apply here, with everyone trying to beat the fastest draw to the drop.
- Evocation is likely to relate to a wizard's personality, perhaps in the appearance of his spells or even just the form of attacks he prefers.