Will allowing all (spell-casting) classes to cast all spells be unbalanced? [closed]

Question

I'm homebrewing a new setting with attendant rule changes. According to the setting all magic comes from the same source. So I was thinking that it might make sense, if wizards were able to case cure light wounds, and clerics cast magic missile.

My basic idea is to open all spells to all spell-casting classes. If a spell is on the class's spell list, it is acquired at that level. If not on the spell list it is acquired at the higher of cleric or wizard level. If not on either of those lists, it is acquired at the highest level of any spell list.

I would also introduce a "spell's known" table for classes that normally know their entire spell list, such as clerics. For wizard's I would probably increase the difficulty/cost of adding spell's to their spellbook (outside of free spells each level).

I'm not looking for any answers about whether this makes sense, or otherwise influences the fluff. I'm purely looking for answers about how this change might affect the balance of the classes and any mechanical problems that might arise.

Answer 1

This would be a huuuuuge balance issue.

Mundane classes were outclassed already, but now you're giving wizards access to every divine spell, essentially doubling their toolkit. Most of all would be clerics, who already have access to their entire spell list with a very good base attack bonus, as well as a useful channel energy ability, and druids, who with access to wizard spells and wild shaping would become monstrous nigh unstoppable forces of nature.

There would be little reason to play as a Sorcerer with this new homebrew, as Sorcerer's already don't have enough spells to choose from as-is, and Bards, Rangers, and Paladins would get a boost in power in the early levels but it wouldn't be substantial at later levels due to them not having access to the higher tiers of spellcasting without being given the option to progress their spellcasting further.

With access to Divine Power from the Cleric spell list there's almost no reason to play a mundane character any more with these changes, as once you have access to fourth level spells you can buff yourself up with Bull's Strength and Divine Power and crush anything in your path with either melee or magic depending on what the situation calls for.

Answer 2

Spellcasters are already vastly more powerful than non-spellcasters, and you are worsening that gap in the system. I'm not sure this counts as a balance issue, because it's already a problem to such a degree that non-spellcasting classes generally can't compete with spellcasters even at level 1.

However, some classes-- the ranger in particular-- have incredibly powerful exclusive spells (like Instant Enemy) that are even more powerful for full-casting classes like the Wizard and Cleric, who get slots of the required level much, much sooner. This change will make all partial-casting classes worthless, since access to other classes' low-level abilities later in the game cannot possibly make up for those classes gaining your late-game abilities early in the game.

The inclusion of psychic spellcasters like the Occultist would be additionally problematic: the Occultist is usually limited by an extremely small list of spells, but now has access to all spells ever (additionally problematic since this presumably trumps the Occultist's school restrictions).

Sin Magic Specialists get a huge bonus, as their 'prohibited schools' penalty shtick no longer inhibits them in any way, and they essentially get +2 spell slots of each level. They still are some of the worst schools when played straight; lacking school abilities.

Depending on the Spells Known feature, I'm guessing Clerics are going to be (relatively) nerfed, pushing Wizards solidly ahead in terms of class ratings. If the Spells Known feature gives Clerics a number of spells known at each spell level equal to the number of spells on the currently existing Cleric spell list, however, the Cleric will remain about as good as the Wizard.

I think the classes most benefited by this change, however, are the Witch and the Shaman, who ordinarily get awesome powers in exchange for a sucky spell list. The extra spells aspect of Patrons no longer makes sense, of course, but having full casting, occasional early entry into some spells, and extra abilities the regular full-casters don't get put these classes up to t1 in my opinion, under the new rules. Particularly the Witch, who, like the Wizard, can add spells to her familiar with loose change (especially if you, like you say in the question, only increase the cost of learning new spells for wizards specifically)

I don't know if you count Alchemist stuff as spells, but if you do, there are going to be a lot of weird consequences with extracts and stuff of spells you can't normally make it that form.

Ultimately, though, your system doesn't meet your title:

This isn't "all classes can cast all spells". This is "full casting classes can cast all spells". Rangers will still only ever get up to 4th level spells, Summoners 6th, Fighters none, etc. This is mostly a massive worsening of already existing tier issues, with some slight reordering on the side.