Does this allow Shillelagh to be cast using Constitution?

Question

At first level select cleric, with the nature domain using the feature Acolyte of Nature to select Shillelagh.

At 1st level, you learn one druid cantrip of your choice. This cantrip counts as a cleric cantrip for you, but it doesn’t count against the number of cleric cantrips you know.

This cantrip counts as a cleric cantrip for you, so next level up Sorcerer, with the Divine Soul subclass. Select Shillelagh as your cleric cantrip.

When your Spellcasting feature lets you learn or replace a sorcerer cantrip or a sorcerer spell of 1st level or higher, you can choose the new spell from the cleric spell list or the sorcerer spell list. You must otherwise obey all the restrictions for selecting the spell, and it becomes a sorcerer spell for you.

Now this spell becomes a sorcerer spell for you. Finally when you have the option to gain a feat, select Aberrant Dragonmark, again selecting Shillelagh.

You learn a cantrip of your choice from the sorcerer spell list. In addition, choose a 1st-level spell from the sorcerer spell list. You learn that spell and can cast it through your mark. Once you cast it, you must finish a short or long rest before you can cast it again through the mark. Constitution is your spellcasting ability for these spells.

If everything is legal, you should have 3 variants of Shillelagh, one using Wisdom, Charisma, and Constitution as their spellcasting ability.

Related: Can you choose same spell twice from different sources? What makes a spell being cast considered to be a {class} spell?

Answer 1

No

Under Divine Soul Sorcerer the phrase is:

...from the cleric spell list or the sorcerer spell list

When you learned the spell as a Cleric, it doesn't add it to the cleric spell list. It is still a Druid spell and found only on the druid spell list.

Same with the Aberrant Dragonmark:

...learn a cantrip of your choice from the sorcerer spell list.

Once again, it only allows you to select from the default sorcerer spell list.

When you took Shillelagh as a cleric, it became a cleric spell to you. But the other features refer to a specific list, not your spell list.

Answer 2

No.

Both Divine Soul and Aberrant Dragonmark cause you to learn a cantrip from a certain spell list. You aren't learning Shillelagh; you already know it. If you were allowed to learn it a second time (it's not clear that you can), then it's still not on the cleric or sorcerer spell lists. The version of it that's a cleric spell is the one you already know, not the one you're trying to learn.

Answer 3

No, but you can cast Shillelagh using Constitution

I think MivaScott is right that you can't add shillelagh from your Sorcerer Spells Known to the options available when you take the Aberrant Dragonmark and choose "a cantrip of your choice from the sorcerer spell list".

But you can cast shillelagh using constitution if you can:

• find the (uncommon) Fochlucan Bandore musical instrument magic item;
• take at least one level of Bard so that you can attune to it;
• take the Aberrant Dragonmark feat so that constitution is one of your spellcasting abilities;
• and, then using the fact that (Dungeon Master's Guide, p. 141):

A magic item, such as certain staffs, may require you to use your own spellcasting ability when you cast a spell from the item. If you have more than one spellcasting ability, you choose which one to use with the item.

Despite being a bonus action cantrip, the wording of the Instrument of the Bards magic items suggests that you may only be able to cast shillelagh once per day, as an action, by playing your Bandore (Dungeon Master's Guide, p. 176):

You can use an action to play the instrument and cast one of its spells. Once the instrument has been used to cast a spell, it can't be used to cast that spell again until the next dawn. The spells use your spellcasting ability and spell save DC.

However, if I was a DM and a player had gone to the trouble of tracking down the wondrous Fochlucan Bandore, I might treat it like a normal cantrip since it's the only cantrip on the Instrument of the Bards list of all seven instruments and their spells, and the Fochlucan Bandore is the only instrument with a cantrip in addition to three other spells.

Answer 4

Depends on what you think 'This cantrip/spell counts as a [class] spell' means.

To me, a 'cleric spell' is a spell from the cleric spell list, cast using the ability score clerics use, and otherwise following any specific rules cleric spells have that spells for other classes don't. If Magic Missile counts as a cleric spell for you, then it does so regardless of which class ability is affecting Magic Missile later.

However, people will die on this hill. Few people would dispute that a spell counting as a Sorcerer spell despite being on the Cleric spell list could not benefit from a Sorcerer ability saying that you could add cha to the damage of a sorcerer spell, or something. However when you are transforming a spell through multiple abilities, especially with some kind of flashy sounding (but actually kind of dubious) payoff that 'seems strong' to the first glance of people not particularly heavy on math, people will try to find something to disagree with and any ambiguity (even a nonexistent one) will become a point of contention.

So is this the most logical reading of those abilities? Almost certainly yes, i'd say. Will people, up to and including the designers of the game, say it's wrong and not RAW? Also almost certainly yes.

There's enough ambiguity to argue, and it's the kind of '3v1l munchk1n ch33z' that will attract arguments.

So whether or not this ability will be read one way or another will depend on the table and the DM.