Wall of Bones

You create a wall of sharp, robust, stiff, interlocking bones. The wall appears within range on a solid surface and lasts for the duration. You choose to make the wall up to 30 feet long, 20 feet high, and 5 feet thick or a circle that has a 10-foot diameter and is up to 20 feet high and 10 feet thick. The wall blocks line of sight. 

When the wall appears, each creature within its area must make a Dexterity saving throw. On a failed save, a creature takes 5d6 piercing damage, or half as much damage on a successful save.

Each 5 square foot segment of the wall has 10 hit points, 15 AC, resistance to piercing damage, immunity to poison and psychic damage, and immunity to all conditions. Portions of the wall cannot remain airborne, and collapse if not affixed to an adjacent wall or the ground.

If a creature you don't consider an ally within 5 feet of the wall moves further away from it, the wall makes a melee spell attack roll with your spell attack bonus (ala attack of opportunity) against it, as skeletal appendages shriek towards it. On a hit, the target takes 2d8 piercing damage and must succeed on a strength saving throw against your spell save DC or be pulled back within 5 feet of the wall.

If you concentrate on the spell for the full duration, it becomes permanent unless destroyed or dispelled.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, you can use your bonus action (while concentrating on the spell) to cause a skeleton to extricate itself from the wall. The skeleton follows your commands (no action required) and will defend itself, you, your allies, and the wall if given no other instructions. You can extricate a total of eight skeletons from the wall over the duration of the spell, replacing any that have been defeated. The skeletons disappear when the spell ends unless you saw it through to permanency. Then the skeletons will simply defend you your allies, and the wall, but no longer take commands, and will not willingly move 60 feet beyond the wall. If the wall is destroyed, the skeletons collapse into piles of dust.