Undead Ward

The line you etched in the floor shines like ivory in moonlight, and the skeletons stop advancing.

You create a magical barrier against undead creatures. This barrier can be a closed circle, with a 30ft radius or a 30ft by 30ft cube.

An undead creature whose level is lower than your character level cannot pass through the barrier, affect creatures through the barrier, or affect the barrier in any way. Any other undead creature takes 2d8 radiant damage when passing through the barrier, but doing so breaks the barrier and ends the effect.

Any creature able to pass through the barrier can take an action to obscure the inscription and thereby break the barrier.