Magic:Glyph of Warding

Abjuration [ Sonic ]
Level: Clr 3
Innate Level: 3
Component(s): V, S
Casting Time: Instantaneous
Range: Short
Target: Large
Duration: 1 Minute/2 Levels
Counter(s): --
Saving Throw: Reflex 1/2
Spell Resistance: Yes
Metamagic: Empower, Extend, Maximize, Quicken, Silent, Still
Energy Substitution: No

The caster creates a small, magical zone that can detect the passage of enemy creatures. When the field is activated, it explodes, doing 1d8 points of sonic damage per two caster levels to all creatures within the area of effect (to a maximum of 5d8). After being triggered, the glyph dissipates.