The Pact (EAFW)

The pacts forged by the elemental beings with the mortals who serve them are strange and terrible contracts. The elementals demand nothing less than the entire lives of the clerics, spent in total service and obedience to the planner entities. In exchange, the elementals bestow what powers they have to give upon their priests. Some are great, some weak, but all of them demand the clerics' total commitment
The pact is "signed" during the priest-candidate's initiation, if he or she succeeds—failure means insanity, death, and occasionally even worse fates. Violations of the various pacts are dealt with quickly and without pity.