For the love of order
Since the events of On the road from the fulcrum, each full member of the party has a small flask that radiates overwhelming magic (at least until we use the polishing cloth on it), cannot be stolen, and can be called upon as a not-an-action. Aramus found himself in possession of one after the party had accepted him as one of the group. The party is not certain whether Dolg’s stayed when he and we parted ways, or if it has since disappeared.
Only one of them has been used thus far: Gilly’s was employed (without conscious effort on her part) to grant her a personal audience with Thais, at which Gilly’s worldview changed drastically.
Current known holders of overwhelming flasks, then, are: Syama, Aramus, Victor, and Maral.