When you cast this spell, you inscribe a glyph that later unleashes a magical effect, either on a surface (such as a table or a section of floor or wall) or within an object that can be closed (such as a book, a scroll, or a chest) to conceal the glyph. If you choose a surface, the glyph can cover an area of up to 10 feet in diameter. If you choose an object, that object must remain in its place; if the object is moved more than 10 feet from where you cast this spell, the glyph fades, and the spell ends without being triggered.
The glyph is nearly invisible and requires an Intelligence (Investigation) check against your spell save DC to find.
You decide what triggers the glyph when you cast the spell. For glyphs inscribed on a surface, common triggers include touching or standing on the glyph, removing an object placed on the glyph, approaching within a certain distance of the glyph, or manipulating an object on which the glyph is inscribed. For glyphs inscribed within an object, common triggers include opening the object, approaching within a certain distance of the object, or seeing or reading the glyph. Once the glyph is triggered, the spell ends.
You can further refine the trigger so the spell activates only under certain circumstances or based on physical characteristics (such as height or weight), creature type (for example, only aberrations or drow trigger the glyph), or alignment. You can also set conditions for certain creatures not to trigger the glyph, using a password, for example.
When you inscribe the glyph, choose one of the following magical effects:
Explosive Runes. When triggered, the glyph erupts with magical energy in a 20-foot-radius sphere centered on the glyph. The sphere spreads around corners. Each creature in the area must make a Dexterity saving throw, taking 5d8 acid, cold, fire, lightning, or thunder damage on a failed save (your choice when you create the glyph), or half as much damage on a successful one.
Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph, casting it as part of creating the glyph. The spell must target a single creature or an area. The stored spell has no immediate effect. When the glyph is triggered, the stored spell is cast. If the spell has a target, it targets the creature that triggered the glyph. If the spell affects an area, the area is centered on that creature. If the spell summons hostile creatures or creates damaging objects or traps, they appear as close as possible to the intruder and attack. If the spell requires concentration, it lasts for the spell's full duration.
When you cast this spell using a 4 or higher is level, the damage explosive runes increased by 1d8 for each level of top slot 3. If you create a glyph spell, you may store a spell whose level is equivalent or less to spell slot used for the custody of the glyph.