Do you have to do full damage with a cantrip?

[HappyDaze]

At 5th level and above, can you "undercast" a cantrip to do less dice of damage than your maximum? Reasons for doing this might include not wanting to risk inflicting Instant Death against a badly hurt opponent or maybe wanting to just use a secondary effect (e.g., using Thorn Whip to pull a friendly creature).

[micahaphone]

I don't believe RAW says anything about this, but given that the reason your cantrips do more is that you've learned how to put more pepper into even your most basic casting, I see no reason not to make this a thing. Definitely ask a DM, but unless your character is a wild magic sorcerer who's constantly surprised by the force of their own magic, I think it makes sense that you'd have enough control of your magic to pull your punches.

[HappyDaze]

In a related question, does a Warlock have to use the full level of his/her spell slots? Can a 5th level Warlock (with 2 x 3rd level slots) elect to (for whatever reason) cast Armor of Agathys as a 2nd level spell instead of as a 3rd level spell?

[stoutstien]

I think non-lethal attacks are limited to melee attacks to give them a nitche. Knocking a creature out rules allows it with any melee attack so there something.

[Willie the Duck]

Another reason might be to not telegraph how powerful you are (perhaps because you are pretending to be a novice magician or the like).

Regardless, to my knowledge the rules are silent on the issue, but they are also silent on whether you can deliberately shoot an arrow or swing a sword with less force.

[Nikushimi]

In a related question, does a Warlock have to use the full level of his/her spell slots? Can a 5th level Warlock (with 2 x 3rd level slots) elect to (for whatever reason) cast Armor of Agathys as a 2nd level spell instead of as a 3rd level spell?

No. You cannot.

Specifically from the PHB "All of your spell slots are the same level." and "When you are 5th level, you have two 3rd-level spell slots. To cast the 1st-level spell Thunderwave, you must spend one of those slots, and you cast it as a 3rd-level spell."

A Warlock always casts at the highest level spell slot. Always.

They do not have lower level spell slots and thus cannot cast at a lower level. They always cast at the highest possible spell slot.

[BloodSnake'sCha]

I use this rule.
If a player want to weaken himself he is allowed to.

I see this like deciding to fail a roll.

[NecessaryWeevil]

I think non-lethal attacks are limited to melee attacks to give them a nitche. Knocking a creature out rules allows it with any melee attack so there something.

True, although the OP isn't talking about nonlethal attacks, just avoiding instant death.

[Segev]

A warlock who wants to undercast his spells would be advised to take 2-3 levels of Sorcerer. While this is usually to facilitate coffeelocking, in this case what it enables is the conversion of warlock spell slots to sorcery points, and then converting sorcery points into lower-level spell slots from which to cast pact magic. That it also gives a small number of sorcerer spell slots per day in the 1-2 level range only helps with this goal.

That IS a lot of investment for being able to undercast, though.

[JNAProductions]

RAW? No.

Would I allow it? Sure, to both the cantrips and the Warlock undercasting. I would ask if you're trying to pull any wacky shenanigans with it if you asked out of the blue, but I don't really see a reason to not allow it.

[stoutstien]

True, although the OP isn't talking about nonlethal attacks, just avoiding instant death.

I was just pointing out that the ground work was there for controlled strikes.

[NaughtyTiger]

I think non-lethal attacks are limited to melee attacks to give them a nitche. Knocking a creature out rules allows it with any melee attack so there something.

i second this.

i like that using thorn whip on an ally may pull them out of a trap but risk killing 'em in the process.

[JNAProductions]

i second this.

i like that using thorn whip on an ally may pull them out of a trap but risk killing 'em in the process.

Thorn Whip is a melee attack.

[JumboWheat01]

Thorn Whip is a melee attack.

It's a melee SPELL attack, not a melee WEAPON attack. That can change things.

[stoutstien]

It's a melee SPELL attack, not a melee WEAPON attack. That can change things.

The knockout rule just States melee attack not weapon attack.

[MarkVIIIMarc]

I think allowing this is logical, Bob can shoot me in the leg with an arrow instead of my torso so maybe its logical Vicious Mockery can be cast as Moderately Harmful Mockery.

BUT, you are giving an against the rules power to spellcasters. Do something for martial characters and/or melee attacks as well. Maybe toss in the optional flanking rules for example.

[JNAProductions]

I think allowing this is logical, Bob can shoot me in the leg with an arrow instead of my torso so maybe its logical Vicious Mockery can be cast as Moderately Harmful Mockery.

BUT, you are giving an against the rules power to spellcasters. Do something for martial characters and/or melee attacks as well. Maybe toss in the optional flanking rules for example.

The ability to do less damage is nowhere near the ability to gain advantage trivially.

[NaughtyTiger]

Thorn Whip is a melee attack.

ha, you caught me. i was thinking magic attack vs non-magical melee weapon. that said, screw magic, it is already too powerful.

[JNAProductions]

ha, you caught me. i was thinking magic attack vs non-magical melee weapon. that said, screw magic, it is already too powerful.

In what ways?

And is letting a PC save another really that bad?

[MarkVIIIMarc]

The ability to do less damage is nowhere near the ability to gain advantage trivially.

I remember that other thread on flanking. Its an open discussion in my opinion. Guess not yours and we both think we're right of course.

[JNAProductions]

I remember that other thread on flanking. Its an open discussion in my opinion. Guess not yours and we both think we're right of course.

Whether or not flanking is good is subjective. I find it bad, but I am fully aware that that’s my opinion, not a universal truth.

But it seems pretty silly to me to equate undercasting a cantrip to easy advantage.

[RSP]

RAW? No.

Would I allow it? Sure, to both the cantrips and the Warlock undercasting. I would ask if you're trying to pull any wacky shenanigans with it if you asked out of the blue, but I don't really see a reason to not allow it.

Keep in mind, in regards to Warlocks, this allows some benefit with things like a Ring of Spell Storing: a 9th level Warlock could only fill the Ring with one 5th level spell, as opposed to, say, five 1st level Shields.

[JNAProductions]

Keep in mind, in regards to Warlocks, this allows some benefit with things like a Ring of Spell Storing: a 9th level Warlock could only fill the Ring with one 5th level spell, as opposed to, say, five 1st level Shields.

Not a huge deal, I think. Benefit? Yes. OP? Nah. You

Plus, that’d be awesome for the friendly Fighter, who can now get five Shields instead of one, because they’re the frontliner, not the warlock.

[Sigreid]

I would let the caster choose the number of dice up to his normal limit for a cantrip. I don't see any reason he shouldn't be able to pull his punches and a 1 die casting might even be necessary for properly training an apprentice in defensive magical techniques.