Casting time is one hour for the Glyph of Warding, that'd be pretty terrible. No, the casting time is the time it takes the caster to cast the spell. When a spell has a trigger, it activates instantaneously upon being triggered.
To clarify, that still applies to spells stored in the glyph: they activate instantaneously when the glyph is triggered. "Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph by casting it as part of creating the glyph." - the stored spell is cast as part of creating the glyph, so part of that 1 hour.
Does the rune of a Glyph of Warding use the spells casting time at activation?
I.E. Hallucinatory Terrain take 1 min to caste does the rune take 1 min to activate?
Casting time is one hour for the Glyph of Warding, that'd be pretty terrible. No, the casting time is the time it takes the caster to cast the spell. When a spell has a trigger, it activates instantaneously upon being triggered.
To clarify, that still applies to spells stored in the glyph: they activate instantaneously when the glyph is triggered. "Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph by casting it as part of creating the glyph." - the stored spell is cast as part of creating the glyph, so part of that 1 hour.
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