Bone Garden

You curl your finger and the arms of undead humanoids begin to crawl their way from beneath the ground in a 20-foot cube within range. For the duration, the area is considered difficult terrain. When a creature starts its turn or moves into or within the area, it must succeed on a Dexterity saving throw or become restrained. At the start of a restrained creature's turns, it can use its action to make a Strength (Athletics) check contested by your spell save DC, freeing itself on a success.