Wall of Slime

A wall of viscous oozing slime springs into existence at a point you choose within range. The wall is 60 feet long, 20 feet high, and 5 feet thick. The wall is opaque and blocks all vision.

When the wall appears, each creature within its area must make a Dexterity saving throw. On a failed save, a creature is stuck within the wall. on a successful save, the creature takes no damage and can choose which side of the wall to be on.

Any creature that enters the wall or starts its turn there takes 5d10 acid damage, is covered in a patch of green slime, and is Blinded while within the wall. Creatures can move through the wall, but movement within the oozing mass of slime is incredibly difficult. For every 1 foot a creature moves through the wall, it must spend 4 feet of movement. Even when a creature escapes the wall, however many patches of green slime the creature accumulated remain until they are scraped off.

The GM has the statistics for green slime (Page 105 of the DMG)

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d10 for each slot level above 5th.