Detect Decay

For the duration, you sense the presence of corpses and bones within 60 feet of you. If you sense remains in this way, you can use an action to learn one of the following things: what type of creature the corpse is from (humanoid, beast, etc.), the exact location of the remains, or roughly how the creature has been dead for.

This spell cannot identify remains as undead or not, and any undead creatures within the spell's range will register only as whatever physical remains comprise them.

The spell can penetrate most barriers, but it is blocked by 10 feet of stone, 1 foot of common metal, or a thin sheet of lead.