Clarion's Breath

The staff projects an icy blast in a 90-foot cone. Each creature in that area must make a DC 20 Constitution saving throw, taking 67 (15d8) cold damage on a failed save, or half as much damage on a successful one. If the creature critically succeed 0 damage is taken but if the creature critically fails it is incased in ice for 10 minutes and is immune to external damage but is incapacitated, restrained, deafened and stunned so long as it remains fully incased in ice.