New Spell: Column of Ice

3rd-level conjuration
Casting Time: 1 action
Range 100 feet.
Components: V, S, M (a drop of water)
Duration: Concentration, up to 1 minute.

Choose a point you can see on the ground within range. A column of ice erupts in a 10-foot wide by 10-foot long by 20-foot tall rectangular prism centered on that point. This column need not be vertical, but it must be straight. Each creature in that area must make a Dexterity saving throw. Any creature caught in the eruption rises to the new height or is ejected to the nearest unoccupied space if it would be caught between something. If it would be caught, it takes 2d12 damage. The column has AC 12 and 30 hit points per 10-foot section of column and it is vulnerable to fire damage.
At Higher Levels. Casting this spell with at least a fourth level spell slot lets you, if you maintain your concentration for the whole minute, make the column permanent until it melts or is destroyed. If you use a spell slot of fifth level or higher, you may conjure a second column or double the height of the main column, which also becomes permanent at the end of the duration.

NOTE: This spell is based off of the 3.5e Frostburn Spell Column of Ice, the 5e Player’s Handbook Spell Wall of Ice, and the Elemental Evils Player’s Companion Spell Erupting Earth