Cone of Cone

You conjure a 60 ft cone expanding from your finger tips. Each creature within the cone must succeed on a Charisma saving throw or be trapped in a cone shaped demiplane just big enough to fit them in. The cone takes up space in the real world but appears like an ice cream cone it has an armour class equal to your Spell Save DC and 20 hit points. The creature in the demiplane takes 7d6 force damage and 2d8 cold damage. They trapped person is restrained and must use their turn to repeat the saving throw, on a success, the target is freed from the cone, on two failures, the target takes an additional 3d6 cold damage and on their next turn must succeed on a Wisdom saving throw or be changed into a blob of non-sentient ice cream. If the cone is broken from the outside there is a 25 percent chance the cone opens a portal to a random plane of existence and everyone within 30 ft is sucked into the portal which closes immediately afterwards.