Can you store Hex in a Glyph of Warding?

Question

Can you store Hex in a Glyph of Warding?

If a Cleric multi-classes and takes one level in Warlock, would they be able to use Glyph of Warding to store a Hex spell?

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 spell must target a single creature or an area. The spell being stored has no immediate effect when cast in this way. 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 harmful objects or traps, they appear as close as possible to the intruder and attack it. If the spell requires concentration, it lasts until the end of its full duration. (PHB p.245)

Answer 1

Yes, but you can't change targets

Hex can target a single creature.

You place a curse on a creature that you can see within range.

Indeed, the text of hex repeatedly refers to this one creature as 'the target'. This satisfies the requirement of the spell glyph option of glyph of warding.

The spell must target a single creature or an area.

Therefore, you can put hex in a glyph of warding. The hex will be cast on the creature triggering the glyph. Since you are still considered the caster, you (the caster) will deal extra damage to the target per the normal functioning of hex.

However, there is a caveat. Hex can, over its duration, target more than one creature (while still only affecting a single target at a time). A similar question asking 'Can Hex be Twinned?' covers this. Twinned Spell requires that the spell is incapable of targeting more than one creature, and the general consensus leans towards hex not being eligible for being twinned (although there's some wriggle room).

However, glyph of warding is not quite as strong in its wording as Twinned Spell. It says that the spell must target a single creature. This can be read as a constraint on how the spell is to be used in this particular casting, rather than as a constraint on the general properties of the spell. Taking such a reading, this requirement is satisfied if you do not change the target of this hex once they drop to 0 HP. If you consider spells which target 'up to' X creatures, such a spell can target only one creature, so when used in conjunction with glyph of warding it must be cast in such a way to only target one creature. I argue that hex would be a similar case, although uniquely the constraint applies after the spell has been cast rather than during the casting.

If imposing such a constraint on hex seems unreasonable to you, then my argument breaks down and hex would become ineligible for glyph of warding.

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One might get caught up on how the spell glyph specifies that "you can store a prepared spell". One could attempt to argue that this means that only spells from classes who prepare their spells (such as wizards and clerics) are valid and spells from spontaneous casters such as warlocks cannot be used (because they know spells rather than prepare them).

However, such reasoning results in a fallacy, for glyph of warding is also on the bard spell list, and bards are spontaneous casters. This spell would be substantially less useful for them if they could not use half the features. It thus seems absurd to make a distinction between 'known' and 'prepared' spells for glyph of warding. Likely, use of the term 'prepared' is just to clarify that you need to be able to cast that spell today (as opposed to using any spell from your spellbook or the cleric spell list).

See 'Can a Bard use the Spell Glyph option of the Glyph of Warding spell and cast a known spell into the glyph?'

Answer 2

No, hex targets too many creatures

One of the constraints for the spell glyph option of glyph of warding is:

The spell must target a single creature or an area.

Hex targets creatures, not an area, so the question becomes 'who does hex target?' and 'how many targets does hex have?'

A superficial reading of hex gives the impression that it targets only one creature. It is definitely true that the creature you place this curse on is a target of the spell, and you initially only curse a single creature. That creature suffers disadvantage on their saves as a direct consequence of the spell. The spell hex explicitly refers to this creature as 'the target'.

However, this creature is not the sole target of the spell. Hex, over its duration, can target more than one creature by moving the curse to new targets. As discussed in 'Can Hex be Twinned?', hex is ineligible to be twinned by most arguments because it targets more than a single creature. Unlike spells where the number of targets is chosen at the time of casting, hex allows new targets to be allocated dynamically for the duration of the spell, which means hex cannot be prevented from cursing more than a single creature.

Arguments about swapping targets notwithstanding, there is another more insidious complication. Besides debuffing the target, hex also provides a buff to the caster. As argued for hunter's mark, the caster is directly affected by hex so may also be considered a target. This logic is implied in the answer to 'How do multiple castings of Hex affect a creature?' If we accept this reasoning we can conclude that at a minimum two creatures are targeted by hex: the caster and the cursed creature.

Because hex targets too many creatures, both through being able to swap targets for the duration and by also targeting the caster, hex is not eligible to be used with a glyph of warding.