Alarm

From Player's Handbook, page 211.

Description
1st-level abjuration (ritual)


 * Casting Time: 1 minute
 * Range: 30 feet
 * Components: V, S, M (a tiny bell and a piece of fine silver wire)
 * Duration: 8 hours

You set an alarm against unwanted intrusion. Choose a door, a window, or an area within range that is no larger than a 20-foot cube. Until the spell ends, an alarm alerts you whenever a Tiny or larger creature touches or enters the warded area. When you cast the spell, you can designate creatures that won't set off the alarm. You also choose whether the alarm is mental or audible.

A mental alarm alerts you with a ping in your mind if you are within 1 mile of the warded area. This ping awakens you if you are sleeping.

An audible alarm produces the sound of a hand bell for 10 seconds within 60 feet.

Learned By

 * Classes: Artificer, Ranger, Wizard
 * Subclasses: Fighter (Eldritch Knight), Paladin (Oath of the Watchers), Rogue (Arcane Trickster), Sorcerer (Clockwork Soul)
 * Races: Mark of Warding Dwarf
 * Feats: Artificer Initiate, Magic Initiate, Quicksmithing, Ritual Caster