Artificer Armorer Guardian attack and cantrips like Booming blade

Question

So the UA specialist for the Artificer, the Armorer, has an interesting ability for one of the models you can take.

Thunder Gauntlets. Your armored fists each count as a simple melee weapon, and each deals 1d8 thunder damage on a hit. A creature hit by the gauntlet has disadvantage on attack rolls against targets other than you until the start of your next turn, as the armor magically emits a distracting pulse when the creature attacks someone else.

Should you end up with a cantrip like Booming Blade through some means, could you use Thunder Gauntlets to perform it? Would you then get the unique effect of Thunder Gauntlet alongside the normal effects of such a cantrip?

Answer 1

Update regarding the Booming Blade errata (6/9/21)

The Booming Blade errata adds one change relevant to this answer: the weapon used as part of the melee attack must be worth at least 1 sp.

Regarding Thunder Gauntlets, the weapon for Booming Blade would be "your armored fist". So the question (for your DM, probably) is, how much is your armored fist worth?

If you verify your gauntlets/gloves are worth at least a silver, the original answer is still good.

Original answer below:

---

The description of the Booming Blade cantrip says (SCAG, p. 142; emphasis mine):

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, and it becomes sheathed in booming energy until the start of your next turn.

Yes, you can use Thunder Gauntlets as part of Booming Blade

This is because Booming Blade requires a melee attack with a weapon, and Thunder Gauntlets states:

Your armored fists each count as a simple melee weapon

Yes, you would get the debuff effect from Thunder Gauntlets

The spell effect states that the target takes the normal effects of the attack, which includes both the damage and the distracting pulse.

Answer 2

The weapon attack made as part of Booming Blade is a normal attack

Booming Blade says "As part of the action used to cast this spell, you must make a melee attack with a weapon" - since Thunder Gauntlets are melee weapons, you can use them to make melee weapon attacks as part of Booming Blade. This is a normal attack, with everything a normal attack entails. If your attack hits, you would get the unique effect from the Thunder Gauntlets.

Answer 3

Thunder Gauntlets are part of the armour, so you can use Booming Blade if your armour is worth at least 1 sp.

Haravikk settled this argument in this comment, so I will quote them:

Thunder Gauntlets are the armour:

1. You have a suit of armour, e.g- Plate (1,500gp)
2. You have the Arcane Armor feature which adds various bonuses etc. to how you use that armour.
3. You have the Armor Model feature that adds further bonuses depending upon which model you have.
4. One part of that feature is Thunder Gauntlets, which specifies you can attack using the armour's gauntlets if your hands are empty.
5. Gauntlets are part of the armour, you are attacking with the armour, therefore the "weapon" value is the armour value.

Thunder Gauntlets are a separate item:

1-3 are as above. In addition:

• Thunder Gauntlets are a weapon.
• There is no weapon in the Equipment section called "Thunder Gauntlets"
• Thunder Gauntlets have no value.

The problem with this is there is nothing that specifies that Thunder Gauntlets are a separate item to the armour or should in any way be treated as separate from the armour to which they belong, the Thunder Gauntlets feature certainly doesn't. To argue this case requires inventing a step.

Put another way, if someone says "show me where this item is in the book", the obvious response to that is "what item and why?" because the feature doesn't specify an item, and nothing says you must be able to find it in the book under anything other than the item that already exists (the armour).

Ultimately the camp that wants to argue that there is suddenly an item in the game called "Thunder Gauntlets" that has no (defined) value needs to show why this is the case, but that hasn't happened yet.

Even Padded armour is worth 5 gp, so generally all armour is sufficient, see PHB, Chapter 5 Equipment: Armor and Shields.

Answer 4

Yes, Booming Blade can still apply

TLDR; The Thunder Gauntlets can be assumed to be worth well above the 1sp requirement for Booming Blade.

With the official release of the Artificer class and errata on Booming Blade the only key change is the price component requirement for Booming Blade:

Components: S, M (a melee weapon worth at least 1 sp)

Thunder Gauntlets reads:

Thunder Gauntlets. Each of the armor’s gauntlets counts as a simple melee weapon while you aren’t holding anything in it, and it deals 1d8 thunder damage on a hit. A creature hit by the gauntlet has disadvantage on attack rolls against targets other than you until the start of your next turn, as the armor magically emits a distracting pulse when the creature attacks someone else.

So clearly it meets the "melee weapon" part of the requirement but what about "worth at least 1 sp"? There doesn't appear to be any official statement as to the value of these weapons but we can make some comparisons. We're looking at a one handed weapon dealing 1d8 damage and giving disadvantage on other attacks.

Weapons that deal 1d8:

• Battleaxe - 10gp
• Flail - 10gp
• Longsword - 15gp
• Morningstar - 15gp
• Rapier - 25gp
• War pick - 5gp
• War Hammer - 15gp

In terms of what it may be "worth" - a weapon dealing 1d8 of damage, using the above as a comparison, must be worth at least 5gp using the official pricing. The addition of granting disadvantage can only increase that value. The Thunder Gauntlets can be assumed to be worth well above the 1sp requirement for Booming Blade.

For reference here are some examples of items worth 1sp (if the gauntlets were valued at the same level as these items it would still qualify for booming blade):

Club, dice, oil flask, parchment(one sheet), sling.