Trace

Focus on a magical phenomenon that you can see within 15 feet of you for the duration of the casting of the spell. Upon resolution, the object used in the casting of the spell becomes directed towards the original caster of the magical effect. If the target caster is either deceased or not on the same plane of existence as the spell caster at the time of the spell's resolution, the spell fails and still consumes a spell slot.

If the spell succeeds in finding a caster to target, make a spell attack roll against the caster's spell save DC. If the roll fails to meet or beat the DC, the target caster is immediately made aware that somebody is attempting to divine their location and they are able to sense the direction of the caster of this spell for as long as the spell is active.

At higher levels:
If the spell is cast at 5th level or above, the duration extends to 8 hours, no longer requires concentration, and no longer fails if the target caster is deceased. A faint green aura shrouds the object in the case of a deceased target.

At 7th level, the duration is 24 hours, and no longer fails if the target caster is on another plane of existence. Instead, the item seems to spin helplessly. If used during the casting of the Plane Shift spell or other similar method of traversing planes, the item can serve as an anchor to direct the traversal method to the same plane as the target caster.

At 9th level, the spell lasts until willingly dropped.