Embrace from Below

You curl your fingers and skeletal arms begin to crawl their way up from beneath the ground in a 20 foot radius centered on a point within range. For the duration, the area is considered difficult terrain, and creatures other than undead have disadvantage on attack rolls made while within it. When a creature that isn't undead starts its turn or moves into or within the area, it must succeed on a Dexterity saving throw or become grappled as the skeletal hands grab them. As an action, a creature grappled by the skeletal grasp may attempt to escape from the grapple, making their choice of a Strength (athletics) or Dexterity (acrobatics) ability check, contested by your spell save DC. Any creature that can reach the grappled target may use its action to attempt to break the target's grapple by succeeding on the previous contested check. 

As an action on your turn while you maintain concentration on this spell, you may drag any creatures grappled by the skeletal hands into an early grave. When you do so, each creature grappled by the skeletons must succeed on a Strength saving throw or become prone, blinded and restrained while grappled this way, and begin to suffocate as the undead arms begin to pull the creature down into their earthly demise. On a successful Strength save the creature remains grappled but does not have any further effects befall them. A creature restrained by this spell may still use its action to attempt to break free from the grapple.

A creature that dies while grappled by the skeletal arms is buried in the nearest available space that is at least six feet below ground.