Stasis is a supernatural and magical condition in which an individual or an object has been locked into an energy field where it cannot interact with outside world, nor can it be affected from the outside. Stasis-fields appear also to stop or slow time for the interior of the field. Moreover, it is possible to lock an individual or an object only partially to such a field. An example of this was present during the Empire-Avernum War when a prisoner was held in quasi-stasis in one of the cells of the Castle for interrogation.
Another such incident is reported to have happened a long distance west from the Tower of Magi (vaguely sometime during the Empire-Avernum War or a little bit before that) where a platoon of mages and demons had been locked to a large stasis-field. It remains unknown whether this was a desperate last measure on the mages' part for trying to hold out until help would arrive or a twisted, sadistic trick performed by the demons -- a band of adventurers told that upon their arrival the battlefield de-froze and the demons made short work of the mages and turned against the adventurers next. The demons were slaughtered to the last imp and as thus no witnesses remained alive to tell of the truth. This example implies, however, that either several casters may unite their efforts in order to cover entire fields into a stasis, or that a single extremely powerful magician may perform such a feat of strength.
Stasis as a magical spell is rather difficult to learn and as thus it is not a usual spell among of travelling mages, namely adventurers.