4-level Necromancy
A cage made of iron and bone, with small sharpened spikes running along the sides surrounds a target within range. The target must make a Dexterity Saving Throw or become trapped within the cage. While caged, the target is restrained and takes 1d8 piercing damage at the start of their turn. On a successful saving throw, the target is neither restrained and takes no damage. The Cage has 50 hit points and 10 AC.