D&D 5E Arcane Trickster + Green-Flame Blade = Sneak Attack dealing fire damage?

the_move · Mar 25, 2016

As told by the sage advice an arcane trickster can combine the Green-Flame Blade cantrip with his Sneak Attack under the right circumstances, since Green-Flame Blade includes a weapon attack.

The cantrip description tells that at 5th level the attack deals an extra d8 fire damage to the primary target. This means that the attack deals both fire damage and (most probably) piercing damage damage.

According to this is the arcane trickster able to choose his Sneak Attack to deal either extra fire, or piercing damage?

bid · Mar 25, 2016

Note that you cannot use TWF with GFB since you aren't using the attack action. That means you don't get a second chance of landing you SA.

I've always assumed stat mod damage and GWM/SS used the same type as the weapon but I cannot find where it is explicitely stated. I'd assume SA uses the same. Still, fire or thunder would make sense.

the_move · Mar 25, 2016

Note that you do not need an attack action to deal Sneak Attack damage, but only need to attack with a finesse weapon, or a ranged weapon, the latter being disqualified by GFB. Otherwise SA would not work with opportunity attacks or Commander's Strike (reaction). GFB includes a melee attack with a weapon. Also dual wield is not desirable for my char build, as he would use his Cunning Action (dash) with the Mobile feat (80 feet total speed ignoring difficult terrain and the attacked creature can not OA him).

Kithas · Mar 25, 2016

the_move said:
Note that you do not need an attack action to deal Sneak Attack damage, but only need to attack with a finesse weapon, or a ranged weapon, the latter being disqualified by GFB. Otherwise SA would not work with opportunity attacks or Commander's Strike (reaction). GFB includes a melee attack with a weapon. Also dual wield is not desirable for my char build, as he would use his Cunning Action (dash) with the Mobile feat (80 feet total speed ignoring difficult terrain and the attacked creature can not OA him).

If i recall corrctly anytime a spell or ability adds non-specified damace to an attark it is the sawe damage that weapon would normally produce. That said it is somewhat vague so check with your dm.

the_move · Mar 25, 2016

Well, the Sneak Attack's paragraph does not say it deals the same type of damage as the weapon, although plausible.
The paragraph says the attack deals an extra xD6 damage. But the attack done with the GFB at lvl 5 and above deals weapon/piercing damage as well as fire damage. So far I also have not found a hint inside the PHB and DMG.

Kithas · Mar 25, 2016

the_move said:
Well, the Sneak Attack's paragraph does not say it deals the same type of damage as the weapon, although plausible.
The paragraph says the attack deals an extra xD6 damage. But the attack done with the GFB at lvl 5 and above deals weapon/piercing damage as well as fire damage. So far I also have not found a hint inside the PHB and DMG.

As i said since its unclear ask your dm. Hunter's mark werks the same way.

Colder · Mar 25, 2016

The GFB description says that "the target suffers the attack's normal effects, and green fire leaps from the target to a different creature..."

Sneak Attack would be considered one of "the attack's normal effects," so sneak attack would only increase the weapon damage, not the fire damage. That's how I read it, at least.

the_move · Mar 25, 2016

Right, but that sentence is referring to lvl 1-4, where the attack itself does no fire damage to the primary target.
This is replaced at lvl 5 by "The melee attack deals an extra 1d8 fire damage to the target, and the fire damage to the second creature..."
At that time the primary target suffers more than the attack's normal effects, and it's also questionable if Sneak Attack is a weapon's normal effect. Afaik it's a class feature.

Kithas · Mar 26, 2016

the_move said:
Right, but that sentence is referring to lvl 1-4, where the attack itself does no fire damage to the primary target.
This is replaced at lvl 5 by "The melee attack deals an extra 1d8 fire damage to the target, and the fire damage to the second creature..."
At that time the primary target suffers more than the attack's normal effects, and it's also questionable if Sneak Attack is a weapon's normal effect. Afaik it's a class feature.

Any time sowething says it deals "an extra xdx's" it isnt modifying the weapons damage but adding to it. Anything else that refers to the weapot damace still only finds the bare weapon. Again though talk to your dm if this is important to you 5e is much more based on dm discretion than previous editions so persuading us means nothing.

the_move · Mar 26, 2016

This is less about persuasion, but about if anyone has seen a paragraph clearly dealing with that issue. However, I'd take it as "based on the weapon damage", but that also implies if the weapon itself deals nonphysical damage - like a Sunblade dealing radiant damage only - the Sneak Attack's damage will become radiant as well.