Torrential Avalanche EPIC Tier 2

A gigantic avalanche of snow and debris appears at a point you choose within range.

You can make a wall of snow in a straight line up to 500 feet long, 100 feet high, and 50 feet thick, which lasts for the duration.  The wall is permeable, requiring 4 feet of movement for every 1 foot a creature wishes to move through it.  When the wall appears, each creature within the area must succeed on a Strength saving throw or take 10d10 cold damage, or half as much on a success, and become immersed within the wall.

At the start of each of your turns after the wall appears, the wall, along with any creatures in or on its affected area, moves 60 feet in a straight line away from you.  Any Gargantuan or smaller creature immersed within the wall or whose space the wall enters when it moves must attempt a Strength saving throw or take 10d10 cold damage, or half as much on a success. A creature can take this damage only once per turn. If the wall lasts for its full duration, it crashes to the ground in a wave of frigid cold. Each creature within the wall’s area when the spell ends in this manner must succeed on a Dexterity saving throw or take 30d10 cold damage, or half as much on a success.

When you cast this spell as a ritual, its casting time increases to 8 hours. When you cast the spell in this manner, its maximum length is increased up to 1 mile, its maximum height is increased up to 1,000 feet, and its maximum thickness is increased up to 500 feet.