Summon magic (or alternatively, conjuration magic) is interesting. It brings a person, place or thing from one location to another (the location of the summoner, or conjurer), generally speaking. I’ve seen it handled a few different ways — namely in games like Magic: the Gathering, Diablo, Arcanum, Final Fantasy, and Dungeons & Dragons — and the types of summons, the rules of summoning, and the mechanical aspects vary across all of them.

In Dungeons & Dragons Third Edition, summoning was differentiated from calling. Whereas the former created a simulacrum of the “summoned” creature to support the caster, which otherwise acted in all ways similar to the original (with a few limitations, namely on summoning additional allies), the latter brought the “called” creature physically to the side of the caster. A summoned creature could be destroyed with no negative repercussions, while a called creature could be slain, making it hazardous.

Summoned creatures (including many player-controlled undead) in the Diablo and Warcraft ‘verses appear to be magical constructs, sustained by the mage who created them. Undead raised by necromancers in Warcraft 3 have a time limit, and if I remember correctly, can be destroyed by spells that specifically target summons. In either case, the summons appear on the battlefield and directly aid the spellcaster.

In the majority of games in the Final Fantasy series (mainly excluding 10 and 12), summoned creatures appear on the battlefield to deliver a single attack and then vanish — functioning more like channeling magic than “summoning” (I’d compare it more to Turn Undead from D&D, and similar evocation powers), though you could arrive at either just as easily, I suppose. *ponders*