Dvebl conjuration

Summoning of the arcane dwarvish style, involving the immediate appearance of an extraplanar being, dates back to Alec van Kolk, High Richter of the Dvebl kingdom in the early days of the Dvebl-Kahalit Wars. It was van Kolk who taught dwarvish wizards the precise phrasing that can call and bind devils, demons, and angels. While modern wizardry would refer to this as a spell, to these dwarves it was more akin to a legal agreement: if the wizard executes their verbiage properly, the extraplanar party is contractually obliged to perform their duties, and bound by all applicable terms and conditions. Of course, ambiguous language or loopholes left by the caster leaves the summoned creature free to inflict all manner of horrible violence on its would-be employer.
As these legal formulae, properly executed, result in a contract that cannot be refused by the summoned party, many Dvebl scholars came to believe that van Kolk had struck deals with extraplanar rulers to enforce these agreements: that the various conjuration spells are simply subclauses of a plane-spanning arch-contract. (It was this feat that the wizards of Project VOC ostensibly tried to replicate, with disastrous results.) However, van Kolk said that the legal framework of modern conjuration was not something he had written but something he had found, in one of his many wanderings through the Abyss. Until the end of his days, van Kolk insisted that there was a law-before-all-laws binding every being in the cosmos, and a great lawgiver who had made it; a law of which the contracts of summoning constitute only a footnote.
While the Dvebl tried to keep the contractual language of summoning a closely-held secret, of course it eventually got out. Clauses of summoning have entered the teachings of many schools of wizardry, and intrepid conjurers have even discovered some new ones (additional fragments, perhaps, of van Kolk's law-before-all-laws). However, the more these legal concepts spread, the less soundly they were executed, and poorly-worded contracts led to hundreds of deaths; entire islets are now populated solely by demons loosed of their contractual obligations and free to rampage. Today, summoning, while not banned outright in the way that pact magic is, is heavily regulated within the Collective. Wizards are required to obtain licenses to summon, and attempting to conjure beyond one's level (or while under the influence of alcohol) is a serious crime.