Corpselight

You imbue the dead with magical energy, causing all corpses, bones,
and Undead creatures within range to emit 15 feet of dim light in a
color of your choice. The light in no way hinders Undead creatures other than revealing the presence of invisible Undead creatures.
You can end this spell as a bonus action on your turn.
If this light is blocked by a barrier, it can be seen as a faint
flicker if the barrier is less than 3 feet of stone, 3 inches of common
metal, or 8 feet of wood or dirt. A thin layer of lead blocks the light
completely.