D&D 5E Limiting use of cantrips - what are the consequences?

[Tony Vargas]

Well that doesn't seem true to me... of course, non-combat cantrips have nothing similar with weapons. But combat cantrips are exactly designed to be a wizard's weapon.

Maybe I'm seeing too pedantic distinction, here, but cantrips are class abilities, while weapons are gear. Proficiency with a weapon, making it a practical choice to make an attack with might be a class ability, but making attacks with weapons is something anyone can do.

/Extra Attack/, for instance, is a class ability that can be used with weapons....

they also made that damage scale to partially keep up with the other classes getting more attacks

...cantrips are like Extra Attack in that they scale up your at-will damage as you level. They are also like Battlemaster maneuvers in that they can do a bit more than just damage.

So... I get that removing/limiting cantrips is something that changes game balance.

In theory, sure, but it's not like there's a lot of theoretical balance designed into the classes as it is. In practice, the DM holds the reigns when it comes to balancing encounters, adventuring days, and managing spotlight balance among the PCs. Shifting theoretical balance a little (or even a lot) won't change that.

Let's assume I do wish to implement a low-cantrip limit. I'm thinking of something pretty straightforward:

number of daily cantrip slots = spellcaster level + ability bonus.

In my campaign(s), I get players through the heroic tier of play, i.e. levels 3-10. So considering what are, for me, level 1 or level 15-20 corner cases, is not relevant.

That further limits the impact of reducing cantrip availability. For a low-level caster, using a cantrip is a lot cooler than making an attack, but it's not vastly more effective. When the best fighters get an Extra Attack at 5th, casters will notice that their attack options once they're out of cantrips are starting to look pretty inferior, but if you never reach 11th, that's the worst it'll ever get.

I would wish to counter-balance this important reduction in spell availability for casters with something. I'm not necessarily looking for total balance in classes.

Balance is something you can manage in play. Shortening the day slightly - consistently having closer to 6 rather than 8 of the standard-issue 6-8 medium-hard encounters/day, for instance - would probably be more than enough. You'd want to be sure that the number of rounds of combat in the day still exceed the available cantrip slots + spell slots, of course, so you don't have spells going off absolutely every round, if you're trying to get a remotely low-magic feel.

The other significant consideration is that if your campaign is at all low-magic, in general - if NPCs are rarely casters and most enemies aren't casters and don't specifically prepare to counter caster threats as a matter of course - then PC casters are going to have an advantage, anyway, as their magic will be unexpected, less likely to be countered, and generally higher-impact than in a more typical high magic D&D campaign.

Firstly how could I modify the iconic caster: the wizard; to have him be a decent character during battles, while having limited cantrip uses as indicated hereinabove?

You could provide alternative Actions that the wizard could take instead of casting a spell or using a cantrip. Wizards are supposed to be very knowledgeable, including about monsters, for instance. Over and above whatever else you allow for knowledge checks, you could allow a Wizard to make a Knowledge check against a particular enemy to give an ally advantage on his next check against that enemy. It'd be something to do on a round when casting a spell or cantrip isn't worth the resource, but plinking with a crossbow feels too undignified to the player.

1) I could allow spells that normally allow a saving throw when they are cast, and then each round, to simply be allowed a saving throw when they are cast.

A power-up to those specific spells, out of all proportion even to the complete loss of cantrips. At the same time, no help to a caster who doesn't happen to know such spells.

I'd also warn against messing with Concentration.

2) I could allow non-cantrip damaging spells to deal 1 additional die of damage.

It might make more sense to boost the damage of cantrips a little, since they're more limited. Maybe a caster could use an action to 'gather power' so that his next cantrip does an extra die of damage, for instance.

3) I could allow some type of bonus to weapon attacks. Any ideas here? I don't mind that they will be behind in melee or ranged combat - I expect that they will. However, perhaps a small... Something... To trail less behind?

It's perfectly OK for them to trail in combat. Bounded accuracy means a wizard's DEX or a Cleric's STR and proficiency with a simple weapon is adequate to contribute in combat, once spells and cantrips are expended. Your casters at level 3-10 will have from 6 - 15 cantrips/day, on top of their spellcasting. Even assuming a 'normal day' of 6-8 fast 5e combats, and thus maybe 20 or 25 rounds, that's still casting something every combat - sometimes every single round of every combat in the day at higher levels and/or on shorter days.

What about the druid and the cleric? They are relatively combat competent. Would they require something to help them along? Or could they rely on their melee capacity to remain somewhat effective?

The Druid's shape-changing should help out more than enough. The Cleric will trail a bit for want of an Extra Attack at 5th level, but that shouldn't matter greatly. Maybe you could let a Cleric 'smite' certain enemies based on his Domain, dealing an extra die of damage against them with weapons, starting at 5th level.

 

[MoonSong]

Finally, the sorcerer and warlock. I don't really understand why sorcerers or warlocks would be more negatively impacted by this than wizards or clerics: I've seen both sorcerers and warlocks mentioned in this thread as suffering more than others. I've only played a little 5E (but plenty of 1E, 3.5E and 4E, and other systems too) and there were none of these classes in both short games I played. And we've played little of these even in past editions. Would someone be kind enough to explain to me how one or both of these classes relies more than wizards on cantrips? I don't seem to be able to figure out by looking through the PHB entry.

I might consider leaving unlimited cantrip use to one of these two classes, this then becoming a signature element for this class.

Basically, warlocks were built around eldritch blast and sorcerers derive all their versatility from their cantrips, no ritual caster at all, and very few spells known, the extra cantrip is about everything they have going for them until higher levels, using metamagic greatly reduces the spells they can cast, so cantrips are key to the feel and overall contribution to the party, in and out of combat.

I would suggest to still give warlocks unlimited eldritch blast as a class feature -or just allow them unlimited cantrips, their spells are more about buffing cantrips than standalones -and simply buff sorcerers on other ways, like with more sorcery points (just a couple more per level), spells known (just a couple more at low levels) and all simple weapons -if cantrips aren't the default combat mode for sorcerers, then bring back the spears- .