How op would this be

[Sir cryosin]

I been reading a book and in that world there are many different types of magic users but how they channel magic or gain the ability to use it differ. So I was thinking about letting casters use any spell from any spell list.

[hymer]

I been reading a book and in that world there are many different types of magic users but how they channel magic or gain the ability to use it differ. So I was thinking about letting casters use any spell from any spell list.

The spell lists are balanced towards whether you have total or partial access, so throwing it completely open would strengthen casters, some more than others. It would make clerics and druids far more versatile, since they would then have access to any spell on fairly short notice. For casters with a short list of known spells, they'd get a boost too, but a smaller one. And wizards would be somewhere in between, and depend rather on how many spells they'd be allowed to get.

Fluff-wise, things would pretty much implode. This could be a good or a bad thing, depending on taste. I don't think I'd like it at all. Spell lists distinguish the classes.

Finally, there's the risk of some unforeseen complications cropping up, when so many combos of spells and class abilities become possible. The bard picking up Swift Quiver is an example of (I think) an unintended consequence of their class ability. These would become far more prevalent by throwing the doors completely open.

[Gastronomie]

Everyone starts using Conjure Animals and Conjure Woodland Beings and Animate Objects and the battlefield becomes overpopulated with minions.

[Fflewddur Fflam]

I been reading a book and in that world there are many different types of magic users but how they channel magic or gain the ability to use it differ. So I was thinking about letting casters use any spell from any spell list.

Ehhhhh, that would be like giving the monk's stunning strike to every martial class, or bardic inspiration to everyone with over 10 Charisma. What's the point of classes being classes if their distinguishing features (and spells) are the same for everyone? At a certain point, you are talking about a game with no more classes. Which is fine if that's what you want but it's no longer D&D.

[Gastronomie]

Ehhhhh, that would be like giving the monk's stunning strike to every martial class, or bardic inspiration to everyone with over 10 Charisma. What's the point of classes being classes if their distinguishing features (and spells) are the same for everyone? At a certain point, you are talking about a game with no more classes. Which is fine if that's what you want but it's no longer D&D.Agreed.

It has a lot of downsides, and no positive influence I can see at the moment. It's honestly an idea that shouldn't be put to actual use, unless every single member of the party is okay with it (which is highly unlikely).

I would agree to, say, giving once-per-long-rest Animate Dead to a Fiend Warlock with Orcus as his patron, and other "fluff" stuff like that, but this is a different matter.

[Specter]

The Bard's magical secrets would be worthless.

[RickAllison]

The Bard's magical secrets would be worthless.

See, this is the first compelling argument I've seen for this modification :smalltongue:

[ES Curse]

Also makes Domain/Circle spell features pointless. Plus, the Warlock's spell list was balanced around getting spell slots back on a short rest vs everyone else needing a long rest, so you may have some goofiness coming from that.

[hymer]

The Bard's magical secrets would be worthless.


Also makes Domain/Circle spell features pointless.

Badly degraded, certainly, but not actually worthless or pointless. They still add to spells known or spells prepared, respectively.

[R.Shackleford]

I been reading a book and in that world there are many different types of magic users but how they channel magic or gain the ability to use it differ. So I was thinking about letting casters use any spell from any spell list.

Not OP at all.

Though I would suggest only letting the Sorcerer do this. It fits the fluff of "they don't learn magic, they are magic" so I don't see why they would be stuck in one list...

[SaintRidley]

Fluff wise, you can just as easily say the current system already is this without having to change spell list access.

[bid]

I been reading a book and in that world there are many different types of magic users but how they channel magic or gain the ability to use it differ. So I was thinking about letting casters use any spell from any spell list.
Isn't that somewhat what domain spell does?

I would allow any caster to define its "known spells domain" as it sees fit, like UA sorcerer did (known, not able to learn). I would allow druid/cleric to change domain by spending some time at a temple.

But not a free-for-all every morning.

[Naanomi]

Pros:
-slightly easier paperwork for creating casters
-can maybe realize concepts better with open lists (i.e.: ice sorcerer with Druid access; specific themed warlock patrons)

Cons:
-Tome warlock becomes next to useless;
-Some spells become wonky as short-rest spells (animate dead);
-General loss of flavor of casting classes;
-Relatively weaker martial classes (unless they get all their abilities in one 'super-martial class' in a similar way)
-probably some spells that combo weirdly