Alarm

Choose an opening or an area that is no larger
than a 20-ft cube. Until the spell ends, an alarm
alerts you whenever a 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 (ping in your mind, 1 mile) or audible
(10 second ring, 60 ft).
Duration: 8 Hours
Material: Tiny bell, fine silver wire