The Mirror of Life Trapping can trap creatures in it.
Any creature other than you that sees its reflection in the activated mirror while within 30 feet of it must succeed on a DC 15 Charisma saving throw or be trapped, along with anything it is wearing or carrying, in one of the mirror’s twelve extradimensional cells.
Does the creature even know it’s making a save for something? If it doesn’t, then it’s likely my players will stand around for a while and I’ll call for multiple saves. Otherwise, they’ll probably look away very quickly.