How to balance a BB/GFB-like cantrip for reach weapons?

[Wasp]

Hi everyone

I was wondering - if you wanted to adapt the greenflame blade or booming blade cantrip to be allowed to be used with reach weapons, how would you go on about it?

I was thinking using a commonly resisted damage type like poison and converting all damage into that type may do trick (together with reducing the dice from 1d8 to 1d6). What do you think?

Poison Blade
Evocation cantrip
Casting Time: 1 action
Range: 15 feet
Components: V, M (a weapon)
Duration: 1 round
As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell's range, otherwise the spell fails.
On a hit, the target suffers the attack's normal effects except the damage type is changed to poison, and the target becomes surrounded by oily black smoke until the start of your next turn. If the target willingly moves before then, it immediately takes 1d6 poison damage, and the spell ends.
At Higher Levels. At 5th level, the melee attack deals an extra 1d6 poison damage to the target, and the damage the target takes for moving increases to 2d6. Both damage rolls increase by 1d6 at 11th level and 17th level.

[SVamp]

Most people that are concerned about balance would agree gfb+bb aren’t balanced right now, and the only way to ‘balance them’ is by removing them/making the opportunity cost to get them so high you end up not getting them. (PHB+1 rule in Adventure League play comes to mind: want an Uber race or that neat lvl 2 shadow sword spell, or healing spirit? Or any of the new options from book XYZ, K then, no cantrips for you!)

So with that in mind, the range balanced version is: you cast improved firebolt, it takes the shape of a flaming weapon within 15 ft, otherwise it looks like firebolt. All other mechanics as firebolt. :smalltongue:

But if you’re serious about trying to balance a homebrew, consider that you should balance vs the cost of a feat (spell sniper) + cantrip since that’s what it takes to do what you want without homebrew.

Perhaps something like if your to hit roll is 5 and under, you gain one exhaustion level, regardless of whether you hit or miss, to account for the strain.

[Steampunkette]

I'd suggest looking at Thorn Whip as a point of comparison.

Short range, low damage, adds a little movement to the target rather than anything -particularly- exciting.

So... How about this:

Poison Strike

As part of the action to cast this spell, make a melee spell attack with the weapon used as the material component of this spell against a target within your reach. On a successful hit, the target must make a Constitution Saving Throw or become Poisoned. The target may repeat the save at the end of each of their turns.

At level 5, and every 5 levels thereafter, increase the damage of this attack by 1d6 Poison Damage.


Alternatively, have the Poisoned Strike spell allow multiple "Weapon Attacks" as it scales which do not add any damage of any kind and deal only the weapon's base damage (No Stat Modifier), but force the Constitution save multiple times.

That's if you wanted a Poison based attack.


Alternatively, you could just make an "Arcane Strike" spell attack cantrip where you make a normal melee attack roll but alter all of the weapon's damage to Force or Fire or something, as a way to get past Magic Resistance early on in gameplay with added damage later on as the cantrip levels up.

[JNAProductions]

I'd suggest looking at Thorn Whip as a point of comparison.

Short range, low damage, adds a little movement to the target rather than anything -particularly- exciting.

So... How about this:

Poison Strike

As part of the action to cast this spell, make a melee spell attack with the weapon used as the material component of this spell against a target within your reach. On a successful hit, the target must make a Constitution Saving Throw or become Poisoned. The target may repeat the save at the end of each of their turns.

At level 5, and every 5 levels thereafter, increase the damage of this attack by 1d6 Poison Damage.


Alternatively, have the Poisoned Strike spell allow multiple "Weapon Attacks" as it scales which do not add any damage of any kind and deal only the weapon's base damage (No Stat Modifier), but force the Constitution save multiple times.

That's if you wanted a Poison based attack.


Alternatively, you could just make an "Arcane Strike" spell attack cantrip where you make a normal melee attack roll but alter all of the weapon's damage to Force or Fire or something, as a way to get past Magic Resistance early on in gameplay with added damage later on as the cantrip levels up.

Poisoned is a really strong condition.

I would NOT allow a cantrip to inflict it-especially not with a duration of "Until you make your save".

Plus, that runs into the issue of everything and their mother having poison immunity-meaning in many games, it'll be outright useless, and in the games where it's not, it's too good.

[SVamp]

How about simply house-ruling BB+GFB to work within your weapons range (second target still needs to be within 5ft of your main target) , but if it’s beyond the standard 5ft range, you have a 20% chance to fumble the attack, doing nothing? (So 1-4 on the D20 is a miss) . Or we could still use the exhaustion idea. The rationale is easy enough: it’s much harder to do at range, so it can fail or cause exhaustion from the strain. Would need to play with it, maybe just 1-3 etc

The main advantage is that if someone later in their career takes spell sniper, it ‘fixes’ the drawbacks but it’s still useable until they are able to slot it in.

Lastly if 1-4 chance to miss or chance to miss is seen as too harsh, it could simply make the BB/GFB fail but still let the weapon attack through.

[Wasp]

Thanks for the feedback, I think I should go back to the drawing board and think a bit more about this.

[nickl_2000]

Not saying they are perfect, but here are a couple of BB like cantrips I created for ranged attacks. It may trigger some ideas.

https://drive.google.com/file/d/1THOKmvPVOL2DWqc5jfk4f-c6SDDPRTrH/view?usp=sharing

[Steampunkette]

Poisoned is a really strong condition.

I would NOT allow a cantrip to inflict it-especially not with a duration of "Until you make your save".

Plus, that runs into the issue of everything and their mother having poison immunity-meaning in many games, it'll be outright useless, and in the games where it's not, it's too good.

The duration thing is fair. I meant to limit it to X Turns or a successful save, but since I didn't write up the full stat block and instead wrote out a loose idea of effect text I never went back and included it.

And yeah. With poison-immune targets it becomes a big issue. That was kinda part of balancing it. In low-levels of play it's largely useful, but by mid-tier it's usefulness is curtailed and at high end you're either using it on Humanoids and the occasional monstrosity or not at all.