Four blade cantrips dealing cold, lightning, acid and poison damage.

[Abuzorg]

Once you readily accept the widespread use of Booming Blade and Greenflame Blade in you games, the problem becomes that there is no alternative for the other elements. I've been using those in my different games for a few years now. I would share them in an appropriate format, but I can't post links or images yet, sorry.

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Caustic Blade
Evocation Cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Duration: 1 round
Components: V, M (a melee weapon)

You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the weapon attack's normal effects and a pool of acid fills a 5-foot square on the ground beneath the target until the start of your next turn. If a creature moves into the acid's space for the first time on a turn or ends its turn there, it takes 1d8 acid damage, and the spell ends.

This spell's damage increases when you reach higher levels. At 5th level, the melee attack deals an extra 1d8 acid damage to the target, and the damage a creature takes for ending its turn in the acid increases to 2d8. Both damage rolls increase by 1d8 at 11th (2d8 and 3d8) level and 17th level (3d8 and 4d8).

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Frost-Wind Blade
Evocation Cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Components: V, M (a melee weapon)
Duration: 1 round

You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the attack's normal effects, and it is sheathed in brittling cold until the start of your next turn. If the target performs more than one melee or ranged weapon attack before then, it immediately takes 1d8 cold damage, and the spell ends.

This spell's damage increases when you reach higher levels. At 5th level, the melee attack deals an extra 1d8 cold damage to the target, and the damage the target takes for performing more than one attack increases to 2d8 . Both damage rolls increase by 1d8 at 11th level (2d8 and 3d8) and 17th level (3d8 and 4d8).

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Static-Shock Blade
Evocation cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Components: V, M (a melee weapon)
Duration: 1 round

You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the attack's normal effects, and the air around the target hums with static electricity that shocks the target if it makes any sudden movement. If the target uses a reaction before the end of your next turn, it takes 1d8 lightning damage, and the spell ends.

This spell's damage increases when you reach higher levels. At 5th level, the melee attack deals an extra 1d8 lightning damage to the target, and the damage the target takes from taking a reaction increases to 2d8. Both damage rolls increase by 1d8 at 11th level (2d8 and 3d8) and 17th level (3d8 and 4d8).

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Toxic Blade
Evocation cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Components: V, M (a melee weapon)
Duration: Instantaneous

You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the attack's normal effects, and the target is splashed with a thick poison that seeps into its wounds. If the target has less than half its maximum hit points remaining after taking damage, it takes additional poison damage equal to your spellcasting ability modifier.

This spell's damage increases when you reach higher levels. At 5th level, the melee attack deals an extra 1d8 poison damage to the target, and the damage the target takes when it has less than half its hit points increases to 1d8 + your spellcasting ability modifier. Both damage rolls increase by 1d8 at 11th level (2d8 and 2d8) and 17th level (3d8 and 3d8).

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What do you think? Would you allow those blade cantrips to be used in your game? How would you modify them?

[Jervis]

The actual effect of toxic blade should be.

“On a hit the target suffers the weapons normal effects. After that, nothing happens because they’re immune to poison.” /s

[Greywander]

I remember a while back coming up with an analogue to Booming Blade but for ranged weapons where they take damage if they don't move.

Coming up with good riders is the tricky part. I don't care for the Toxic Blade rider (unlike the other riders, there's no element of choice for the bad guy; at least GFB lets them choose not to stand next to each other), but for the other ones I think you might be on to something. Other rider triggers you might consider are: casting a spell (or using a magical ability), attacking the same target twice, attacking two different targets, missing with an attack, using certain types of movement (e.g. flying), ending their turn within a certain distance of you, talking, and so on. I kind of ran out of good triggers, but that should be enough to get started with.

[Abuzorg]

Thanks for you comments. I am not entirely satisfied with Toxic Blade either, but I wanted to have at least one of those with a mechanic that is more similar to GFB than BB. What I mean by that is that GFB rider damage isn't dependant on the action the target takes (if two enemies are adjacent, the bonus damage just happens). The condition might be easier to achieve for Toxic Blade than BB, but I think that this fact is offset by the fact that you don't always know when the enemy is at 50% HP and, as Jervis pointed out, that it is poison damage. Finding conditions for the rider damage is tricky, but you have a lot of great ideas, thanks!

[Kane0]

Bonus damage if they are affected by the poisoned condition?

[Yakk]

Frost is too good. Me, I'd have it reduce movement speed by 5' (increasing), and you can spend an attack to break the ice (AC 10, HP equal to movement reduction).

For acid, how about a cloud? A 10' cube even.

Another option is to combo acid and poison together.

The shocking one isn't all that inspired. Takes a reaction is so optional and not that strong usually.

[Abuzorg]

Bonus damage if they are affected by the poisoned condition?

I feel it would be very circumstancial no?

[Kane0]

I feel it would be very circumstancial no?

Yes it would be, but also somewhat in the PC's control. You wouldn't be using the Poison option against a creature immune to it to begin with, and if you're taking the Poison bladetrip over the others there's a good chance you're investing thematically into poison, whether that be through just buying/harvesting and applying it normally, taking the Poisoner feat, making use of a Pseudodragon familiar or casting spells like Ray of Sickness, Stinking Cloud even before you get into other homebrew such as new and improved Poison Spray (https://forums.giantitp.com/showsinglepost.php?p=22982257&postcount=5).

It's probably not the best trigger, but it does make some sort of sense if nothing else.

[Yakk]

Poison: End of next turn, take (spellcasting attribute) poison damage.

+1d8 initial/later damage?

Probably too good. Like booming blade but no decision, and only marginally less damage.

Start of next turn, con save or (spellcasting attiribute) poison damage? If you fail two turns in a row, poisoned until end of next turn? (with +1d8 at 5/11/17 naturally)

Sucks to have a 2nd save on a cantrip however.

[Greywander]

If I were to generalize the sorts of riders we might see on cantrips like this, then I would probably do so as thus:

Rider effects are always damage. If the conditions for the rider are met, then extra damage is dealt, usually to the primary target, but (as with GFB) potentially to a secondary target. For levels 1-4, this is also the only extra damage the cantrip inflicts; starting at 5th level the cantrip also inflicts extra damage on the initial hit.

Rider triggers involve tactical choice on the enemy's part. This can mean, as with BB, that the enemy may choose to take or not take certain actions which will trigger the rider. Or it could be more like GFB, where the enemy makes the choice before GFB is used. Enemies can choose not to stand next to each other, but if they choose to do so then the GFB rider is guarantied.

With those in mind, we can consider expanding the idea of blade cantrips beyond just BB and GFB. Non-damage riders can be explored, but will be difficult to balance. Rider triggers should generally revolve around the enemy taking some action after being hit by the cantrip, or having taken some action prior to being hit by the cantrip. This gives the enemy the power to make different choices to avoid triggering the rider, though when the cantrip is used effectively those other choices will be less optimal than the choices which trigger the rider.

So let's see how well the cantrips in the OP actually hold up to these principles.

Caustic Blade
I actually really like this. It's similar to the idea I had of a reversed BB where they take extra damage if they don't move, but it extends that idea to make that particular space a hazard for any creature, not just the original target. I think this one works well. It also means the target can't just move back onto the original square, which a simple reversed BB would probably allow. The one thing I'd be worried about with this is friendly fire.

Frost-Wind Blade
I don't like this as much, if only because enemies with multiattack are super common. I think I'd prefer to see something that prevents them from attacking the same target more than once, or something like that. That way, it doesn't restrict them quite so much, but still offers a meaningful restriction (particularly since focus fire is the optimal strategy in 5e).

Static-Shock Blade
This is another really great one. Reactions aren't super common, but when they happen they're usually pretty important, so I think it strikes the right balance. It won't come up as frequently as something like attacking twice, but when it does come up it will be a really hard decision for that creature to make, whether or not to use their reaction.

Toxic Blade
I don't like this one because there's no tactical decision making involved here; this is just extra damage once a target is below half HP. Instead, perhaps the spell would splash them in poison that causes them to take extra poison damage if they take any piercing or slashing damage before your next turn? Essentially, this would apply poison to the next weapon to hit them, basically. It would depend on them taking another hit, which is something they can control by moving away or using defensive abilities.

Another option is to have the spell create a cloud of miasma around the target, and if another creature (other than you) ends their turn next to the target, then they'll take poison damage and end the spell. This basically inverts GFB by forcing other creatures to move away from the target after the fact, instead of forcing them to not stand next to each other beforehand. I'd probably rename this one to Plague Blade or something.

[Abuzorg]

Yes it would be, but also somewhat in the PC's control. You wouldn't be using the Poison option against a creature immune to it to begin with, and if you're taking the Poison bladetrip over the others there's a good chance you're investing thematically into poison, whether that be through just buying/harvesting and applying it normally, taking the Poisoner feat, making use of a Pseudodragon familiar or casting spells like Ray of Sickness, Stinking Cloud even before you get into other homebrew such as new and improved Poison Spray (https://forums.giantitp.com/showsinglepost.php?p=22982257&postcount=5).

It's probably not the best trigger, but it does make some sort of sense if nothing else.

You are certainly right about that. It also encourages the kind of creativity that I love to see as a DM, but I feel that it being so circumstancial might cause players to snub it. Also, very nice homebrew spells. I will share a few of my own in the future. Just might steal that Poison spray fix.


Poison: End of next turn, take (spellcasting attribute) poison damage.

+1d8 initial/later damage?

Probably too good. Like booming blade but no decision, and only marginally less damage.

Start of next turn, con save or (spellcasting attiribute) poison damage? If you fail two turns in a row, poisoned until end of next turn? (with +1d8 at 5/11/17 naturally)

Sucks to have a 2nd save on a cantrip however.

I like the idea of the poison being a DOT. But as it is you're right in saying that it would be too strong.





Toxic Blade
I don't like this one because there's no tactical decision making involved here; this is just extra damage once a target is below half HP. Instead, perhaps the spell would splash them in poison that causes them to take extra poison damage if they take any piercing or slashing damage before your next turn? Essentially, this would apply poison to the next weapon to hit them, basically. It would depend on them taking another hit, which is something they can control by moving away or using defensive abilities.

Another option is to have the spell create a cloud of miasma around the target, and if another creature (other than you) ends their turn next to the target, then they'll take poison damage and end the spell. This basically inverts GFB by forcing other creatures to move away from the target after the fact, instead of forcing them to not stand next to each other beforehand. I'd probably rename this one to Plague Blade or something.

Two good ideas. I think that since I like the idea of a DOT I would keep the extra damage if the target takes any piercing or slashing (and maybe poison?) damage before your next turn.



Frost-Wind Blade
I don't like this as much, if only because enemies with multiattack are super common. I think I'd prefer to see something that prevents them from attacking the same target more than once, or something like that. That way, it doesn't restrict them quite so much, but still offers a meaningful restriction (particularly since focus fire is the optimal strategy in 5e).


I thought that it was too easy to achieve the extra damage as well. Split your attacks or take extra damage seems like the way to go here.