We're joining a group this weekend. We'll be joining as a Hill Dwarf Armorer and a Rock Gnome Battle Smith at level 5. We're meeting with the DM to work out the particulars of the character, etc, but can the hive mind please help us make sure we've got the mechanics down?
For our purposes, Alvin (Gnome Battlesmith) and Lorna (Dwarf Armorer) are sleeping in the lee of Alvin's Steel Defendeer when they are awakened by the sentry to find the camp under attack by a mix of goblins and ogres. Since they spent the day on the road, Lorna's Arcane armor is in Infliltrator Mode, while Alvin has infused his Heavy Crossbow with Repeating Shot. Both also have Bags of Holding for their other Infusion slot. Lorna has a Homunculus Servant for her other infusion. Initiative rolls put them acting consecutively, Alvin then Lorna
Round 1: Alvin snatches up his Heavy Crossbow, comes up to one knee and using his Steel Defender as cover, fires off two shots* at two attackers within range of his darkvision. He's trying to draw fire away from Lorna.
Lorna uses her action to don her Arcane Armor, grabs her pack and crawls the 10 feet to the woods, looking for concealment. Once inside, her Servant is sent flying 30 feet towards the closest enemy she saw before ducking into cover.
*Still somewhat unsure whether two attacks are making two rolls to hit, then any relevant damages or attack 1 is resolved before attack 2 goes off.
Round 2: Alvin mounts his Steel Defender (small character, medium construct) that takes half his movement, allowing him to move the other 20 feet towards the enemies in the woods. He uses his action to pull a warhammer out of his Bag of Holding, then his bonus action to cast Magic Weapon on it. He can use his Reaction to cast Shield if he comes under attack after the round.
Lorna would have advantage on her attempt to move through the woods unobserved. Her Servant closes with a goblin in the woods and uses Channel Magic to deliver a Shocking Grasp cantrip.
Turn 3: Alvin travels 10 feet to a goblin skirmisher's position. With the Mounted Combatant feat, he has advantage on an attack against the Small creature. If it survives, he can use a Bonus action to have his Steel Defender attack it with Force-empowered rend. He travels another 20 feet* towards an ogre coming up behind the goblin, taking a two-handed grip on his warhammer, and delivers his second attack aided with Booming Blade, then travels ten more feet past the ogre*
Lorna jumps a second goblin skirmisher with a Shocking Grasp cantrip, uses her second attack to launch a Lightning Launcher attack at a second one 30 feet away, and her Homunculus makes a Force Strike on a third one thirty feet beyond that.
Sounds like you overall have a pretty good grasp of the difference between actions, bonus actions, reactions, and other types of activity (like mounting a creature or moving around) that you can do on your turn without actions.
Your question about attacking two targets: usually, when you're attacking with a weapon on your turn, you're taking the Attack action, which permits you to make a weapon attack against an enemy (rolling an attack roll, and rolling damage if that attack roll hits their AC). Both Battlemasters and Armorers have the Extra Attack feature at level 5, which means that single Attack action lets you make two different attacks, either against the same target, or two targets. Each of those attacks has its own attack roll to hit its target's AC, and its own damage roll if it hits.
That works a little different than when you cast a spell like Fireball that may have more than one target. One obvious difference is that it's the enemies rolling saving throws against your save DC when you cast Fireball, not you rolling an attack roll against their AC. But also, when it comes time to roll damage for that Fireball.... you'll roll once, and that damage roll is used for all the various enemies that the blast struck.
That may or may not feel intuitive to you to remember, but I think it helps to remember that your two attacks are different shots/swings, which might be more or less accurate or effective than each other, but you're only casting one spell, which is the same spell no matter how many enemies are caught in it.
Good luck with your game, sounds like you've got a great idea for a complimentary pair of artificers!
You make one attack roll for each attack, one at a time. If you attack twice you make 1 attack roll, and a damage roll on hit, then another attack roll, and a damage roll on hit. You can attack different targets with your attacks.
You use half your movement to mount your Steel Defender (25/2 = 12~ feet). You're left with your mount's full speed (40 feet) and the rest of your own (if you decide to jump down and run at some point).
Seems like you understand the mechanics pretty well!
Turn 3: Alvin travels 10 feet to a goblin skirmisher's position. With the Mounted Combatant feat, he has advantage on an attack against the Small creature. If it survives, he can use a Bonus action to have his Steel Defender attack it with Force-empowered rend. He travels another 20 feet* towards an ogre coming up behind the goblin, taking a two-handed grip on his warhammer, and delivers his second attack aided with Booming Blade, then travels ten more feet past the ogre*
Lorna jumps a second goblin skirmisher with a Shocking Grasp cantrip, uses her second attack to launch a Lightning Launcher attack at a second one 30 feet away, and her Homunculus makes a Force Strike on a third one thirty feet beyond that.
This part here is an error, however. No problem at all to take the Attack and make your first attack against the first target, then move some distance before making the second attack against a second target. No problem to change your grip on your weapon in that time, or even draw an entirely new weapon. But casting Booming Blade is the [Tooltip Not Found] action, not something you can do as part of the Attack action.
Remember when I said "usually" attacking with a weapon is done with the Attack action? Booming Blade is a spell that provides a different way to make an attack with a weapon. But that spell can't just be socketed in as one of your two Attack action attacks, it's its own action. And that action won't let you make a second attack, you'll only cast the spell once and make its one attack.
Same issue with Lorna's Shocking Grasp. It makes a melee spell attack, instead of a melee weapon attack, but again casting that spell is an entire action and not part of Attack and not something that your Extra Attack feature interacts with.
Don't think of spells as just being weapons, even spells that allow you to make a weapon attack or a spell attack as part of casting that spell are their own dedicated [Tooltip Not Found] action.
The final thing I'll add is.... 9 out of 10 DMs will treat riding a mount the way that you've described, but it isn't quite right for the Steel Defender specifically. If you read closely... you'll notice that your Steel Defender doesn't actually share your turn, but rather has its own turn as an independent creature, immediately after your own:
In combat, the defender shares your initiative count, but it takes its turn immediately after yours. It can move and use its reaction on its own, but the only action it takes on its turn is the Dodge action, unless you take a bonus action on your turn to command it to take another action. That action can be one in its stat block or some other action. If you are incapacitated, the defender can take any action of its choice, not just Dodge.
That makes riding it around dynamically in battle.... almost impossible. You can certainly ride it! And you can command it where to move (which it will obey on its turn), and command it to attack (which it will obey on its turn). But attacking a target yourself, then commanding it to carry you off to a second target.... it won't be able to move during your turn.
But again, most DMs would probably be okay with you just merging your turn and your defender's turn together into a single mega-turn, because it feels bad and awkward for a rider to not be able to ride around on their own turn. In fact, riding in general allows you to control a mount on your own turn... so it's not clear if the Steel Defender HAS to keep its normal separate turn, or if you can instead choose to treat it like a controlled mount and merge it with your turn as normal. Presumably, treating it like a controlled mount would give you the benefit of it acting on your turn, but NOT override your ability to command it to take Steel Defender actions other than the limited Dash, Disengage, or Dodge menu that controlled mounts ordinarily have???
Once during your move, you can mount a creature that is within 5 feet of you or dismount. Doing so costs an amount of movement equal to half your speed. For example, if your speed is 30 feet, you must spend 15 feet of movement to mount a horse. Therefore, you can’t mount it if you don’t have 15 feet of movement left or if your speed is 0.
If an effect moves your mount against its will while you’re on it, you must succeed on a DC 10 Dexterity saving throw or fall off the mount, landing prone in a space within 5 feet of it. If you’re knocked prone while mounted, you must make the same saving throw.
If your mount is knocked prone, you can use your reaction to dismount it as it falls and land on your feet. Otherwise, you are dismounted and fall prone in a space within 5 feet it.
Controlling a Mount
While you’re mounted, you have two options. You can either control the mount or allow it to act independently. Intelligent creatures, such as dragons, act independently.
You can control a mount only if it has been trained to accept a rider. Domesticated horses, donkeys, and similar creatures are assumed to have such training. The initiative of a controlled mount changes to match yours when you mount it. It moves as you direct it, and it has only three action options: Dash, Disengage, and Dodge. A controlled mount can move and act even on the turn that you mount it.
An independent mount retains its place in the initiative order. Bearing a rider puts no restrictions on the actions the mount can take, and it moves and acts as it wishes. It might flee from combat, rush to attack and devour a badly injured foe, or otherwise act against your wishes.
In either case, if the mount provokes an opportunity attack while you’re on it, the attacker can target you or the mount.
Similar issues for the Homunculus Servant. It can be ordered to move (which it will obey on its turn), or be ordered to take actions like Force strike (which it will obey on its turn), or you can cast spells through it on your own turn (which it uses its reaction on your turn to deliver), but you can't move it on your turn to get it into position to deliver a spell for you. Its fiddly, a lot of DMs ignore this for familiars and servants and again let the player just take one combined turn for both the PC and its pet.
I would say that the Mount Rules you have listed would override the Steel Defender rules where they overlap if you are riding on the steel defender. That nerfs the SD if you want to control it as a mount, but only in the same way any other creature gets nerfed when you decide to ride on it.
That means that you could let it be independent, and use it as normal, but you can't make it move for you on your turn, or you can control it, and make it move for you on your turn, but give up it's other functions and abilities that aren't allowed for a controlled mount (like attacking). I'd make you choose when you mounted it, and not change it until you dismount it and remount it, or until combat ends and begins again.
Rather than cluttering up this thread with further mounted combat debate, I'm going to hop over into the Find Steed thread that someone just necro'd. :)
Lorna uses her action to don her Arcane Armor, grabs her pack and crawls the 10 feet to the woods, looking for concealment. Once inside, her Servant is sent flying 30 feet towards the closest enemy she saw before ducking into cover.
*Still somewhat unsure whether two attacks are making two rolls to hit, then any relevant damages or attack 1 is resolved before attack 2 goes off.
Lorna doesn't need to don her Arcane Armor if it was light, because she can sleep in it. If it's medium or heavy, and it's probably heavy, needing to don her armor is exactly right. She does not need to crawl and should not crawl: she can stand up for 10 feet of movement, walk 15, and drop prone, rather than crawling 10. She'll still end up prone and hence be more protected from attacks from 10 or more feet away. That assumes a grid, because you said crawl 10, which only makes sense on a grid - if you're not on a grid the numbers change, including the crawl distance, but there's still no need to crawl.
C_C covered this, but to be clear, attack 1 resolves before attack 2. There are a wide variety of situations in which this matters.
Lorna doesn't need to don her Arcane Armor if it was light, because she can sleep in it. If it's medium or heavy, and it's probably heavy, needing to don her armor is exactly right. ...
This isn't actually a rule anywhere in the PHB, but is present as an optional rule that your DM may be using from Xanathar's Guide to Everything. Even before that book was published, however, it has always been such a common assumption for players and DMs, that its probably just good rules to live by.
Round 2: Alvin mounts his Steel Defender (small character, medium construct) that takes half his movement, allowing him to move the other 20 feet towards the enemies in the woods. He uses his action to pull a warhammer out of his Bag of Holding, then his bonus action to cast Magic Weapon on it. He can use his Reaction to cast Shield if he comes under attack after the round.
Lorna would have advantage on her attempt to move through the woods unobserved. Her Servant closes with a goblin in the woods and uses Channel Magic to deliver a Shocking Grasp cantrip.
Just to be clear, the defender has its full movement of 40 available here. It can, of course, carry you 20 feet, since 20 is less than 40, but it could keep going.
C_C covered this, but if the Defender is being an independent mount, it can't move between Alvin mounting it and Alvin doing anything else - its turn comes after Alvin's.
This was covered as well by others, but if the Defender is being a controlled mount, you should be fine - the controlled mount rules force the Defender's turn to merge with yours.
This is doubly illegal.
The Homunculus has to go after Lorna does, so it can't move into position and then deliver Shocking Grasp.
Lorna lacks the necessary special rules to cast Shocking Grasp and Hide on the same turn - I assume by "move through the woods unobserved" you mean "take the Hide action".
Caveat: you don't need an action to just walk quietly, which might lead to a Stealth roll at advantage, but unless the woods are dummy thicc, everyone will still just see you. Actually hiding behind something is what takes your action.
Turn 3: Alvin travels 10 feet to a goblin skirmisher's position. With the Mounted Combatant feat, he has advantage on an attack against the Small creature. If it survives, he can use a Bonus action to have his Steel Defender attack it with Force-empowered rend. He travels another 20 feet* towards an ogre coming up behind the goblin, taking a two-handed grip on his warhammer, and delivers his second attack aided with Booming Blade, then travels ten more feet past the ogre*
Lorna jumps a second goblin skirmisher with a Shocking Grasp cantrip, uses her second attack to launch a Lightning Launcher attack at a second one 30 feet away, and her Homunculus makes a Force Strike on a third one thirty feet beyond that.
I think C_C covered all of the issues here, but I'll cover them too, just to be sure.
As discussed before, if your Defender is an independent mount, its turn comes after yours. If it's a controlled mount, your movement pattern here is legal.
You can't ever cast Booming Blade and make a second attack using the same action without a very special rule letting you do it. Only Bladesingers have said rule, and you aren't one, so you can't.
As an Artificer, you are subject to the "Tools Required" special rule. This means your copy of Booming Blade has two M components, and the only way the warhammer can be both M components at once is if it's one of your infusions. You already said it isn't. That means you can't cast Booming Blade while holding the hammer in two hands - you have to free a hand to touch your required tool (which can be your bag of holding or your crossbow or an actual tool, and you don't need to draw it, so it can be hanging from your belt or whatever). So you can only do this while gripping the hammer in one hand.
Note: the Servant is an infusion, so it can be such a component for Lorna, if she needs - she can grab the Homunculus to be allowed to cast a spell.
You would take an Opportunity Attack from the goblin if it was still alive, and definitely an Opportunity Attack from the ogre.
You can't ever cast Shocking Grasp and make a second attack - same reasoning as in 2, above.
If you fire the LL while still within 5 feet of a goblin, the attack is made with disadvantage.
3 is too harsh. A character can hold a 2H weapon just fine while accessing material components or focuses (other than the difficulties drawing/stowing/dropping them using free object interactions). There’s no rule that every single component must be fondled simultaneously or suggesting that the attack needs to be made simultaneously with you touching your tool, bag, or crossbow. While holding hammer in one hand touch component/focus with the other to cast spell, let go of it and grip hammer with 2H while making attack completing the spell... that's a perfectly valid way to use Booming Blade.
3 is too harsh. A character can hold a 2H weapon just fine while accessing material components or focuses (other than the difficulties drawing/stowing/dropping them using free object interactions). There’s no rule that every single component must be fondled simultaneously or suggesting that the attack needs to be made simultaneously with you touching your tool, bag, or crossbow. While holding hammer in one hand touch component/focus with the other to cast spell, let go of it and grip hammer with 2H while making attack completing the spell... that's a perfectly valid way to use Booming Blade.
Yes. And they have a free hand…. Hand 1 accesses a focus (tool or infused item). Hand 2 “brandishes” the hammer. Components, check, the spell is now “cast”! So now to resolve its effect, they put both hands on their hammer (at worst, dropping the tool/infused item if they were holding it, but all they really needed to do was fondle their worn haversack) and make an attack.
Yea think I'll have to side with C_C here. The spell and the melee attack might be part of the same action but they are distinctly separate events. So holding the hammer with 1 hand during casting and 2 hands during the attack should be doable.
3 is too harsh. A character can hold a 2H weapon just fine while accessing material components or focuses (other than the difficulties drawing/stowing/dropping them using free object interactions). There’s no rule that every single component must be fondled simultaneously or suggesting that the attack needs to be made simultaneously with you touching your tool, bag, or crossbow. While holding hammer in one hand touch component/focus with the other to cast spell, let go of it and grip hammer with 2H while making attack completing the spell... that's a perfectly valid way to use Booming Blade.
Except you don't need a spellcasting focus if you don't need to replace a M component. In the case of Booming Blade, the M component is the weapon, so you don't need to replace it with a focus.
That's not how Artificers work, as I discussed in my post. Artificers modify their spells, as covered in the Artificer rules - for an Artificer, Booming Blade has two M components, only one of which is the weapon. If the weapon is an infusion, it can be both components at once.
We're joining a group this weekend. We'll be joining as a Hill Dwarf Armorer and a Rock Gnome Battle Smith at level 5. We're meeting with the DM to work out the particulars of the character, etc, but can the hive mind please help us make sure we've got the mechanics down?
For our purposes, Alvin (Gnome Battlesmith) and Lorna (Dwarf Armorer) are sleeping in the lee of Alvin's Steel Defendeer when they are awakened by the sentry to find the camp under attack by a mix of goblins and ogres. Since they spent the day on the road, Lorna's Arcane armor is in Infliltrator Mode, while Alvin has infused his Heavy Crossbow with Repeating Shot. Both also have Bags of Holding for their other Infusion slot. Lorna has a Homunculus Servant for her other infusion. Initiative rolls put them acting consecutively, Alvin then Lorna
Round 1: Alvin snatches up his Heavy Crossbow, comes up to one knee and using his Steel Defender as cover, fires off two shots* at two attackers within range of his darkvision. He's trying to draw fire away from Lorna.
Lorna uses her action to don her Arcane Armor, grabs her pack and crawls the 10 feet to the woods, looking for concealment. Once inside, her Servant is sent flying 30 feet towards the closest enemy she saw before ducking into cover.
*Still somewhat unsure whether two attacks are making two rolls to hit, then any relevant damages or attack 1 is resolved before attack 2 goes off.
Round 2: Alvin mounts his Steel Defender (small character, medium construct) that takes half his movement, allowing him to move the other 20 feet towards the enemies in the woods. He uses his action to pull a warhammer out of his Bag of Holding, then his bonus action to cast Magic Weapon on it. He can use his Reaction to cast Shield if he comes under attack after the round.
Lorna would have advantage on her attempt to move through the woods unobserved. Her Servant closes with a goblin in the woods and uses Channel Magic to deliver a Shocking Grasp cantrip.
Turn 3: Alvin travels 10 feet to a goblin skirmisher's position. With the Mounted Combatant feat, he has advantage on an attack against the Small creature. If it survives, he can use a Bonus action to have his Steel Defender attack it with Force-empowered rend. He travels another 20 feet* towards an ogre coming up behind the goblin, taking a two-handed grip on his warhammer, and delivers his second attack aided with Booming Blade, then travels ten more feet past the ogre*
Lorna jumps a second goblin skirmisher with a Shocking Grasp cantrip, uses her second attack to launch a Lightning Launcher attack at a second one 30 feet away, and her Homunculus makes a Force Strike on a third one thirty feet beyond that.
What did we get right, where did we screw up?
Sounds like you overall have a pretty good grasp of the difference between actions, bonus actions, reactions, and other types of activity (like mounting a creature or moving around) that you can do on your turn without actions.
Your question about attacking two targets: usually, when you're attacking with a weapon on your turn, you're taking the Attack action, which permits you to make a weapon attack against an enemy (rolling an attack roll, and rolling damage if that attack roll hits their AC). Both Battlemasters and Armorers have the Extra Attack feature at level 5, which means that single Attack action lets you make two different attacks, either against the same target, or two targets. Each of those attacks has its own attack roll to hit its target's AC, and its own damage roll if it hits.
That works a little different than when you cast a spell like Fireball that may have more than one target. One obvious difference is that it's the enemies rolling saving throws against your save DC when you cast Fireball, not you rolling an attack roll against their AC. But also, when it comes time to roll damage for that Fireball.... you'll roll once, and that damage roll is used for all the various enemies that the blast struck.
That may or may not feel intuitive to you to remember, but I think it helps to remember that your two attacks are different shots/swings, which might be more or less accurate or effective than each other, but you're only casting one spell, which is the same spell no matter how many enemies are caught in it.
Good luck with your game, sounds like you've got a great idea for a complimentary pair of artificers!
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I'm going to make this way harder than it needs to be.
You make one attack roll for each attack, one at a time. If you attack twice you make 1 attack roll, and a damage roll on hit, then another attack roll, and a damage roll on hit. You can attack different targets with your attacks.
You use half your movement to mount your Steel Defender (25/2 = 12~ feet). You're left with your mount's full speed (40 feet) and the rest of your own (if you decide to jump down and run at some point).
Seems like you understand the mechanics pretty well!
Edit: only read your 1st and 2nd round
This part here is an error, however. No problem at all to take the Attack and make your first attack against the first target, then move some distance before making the second attack against a second target. No problem to change your grip on your weapon in that time, or even draw an entirely new weapon. But casting Booming Blade is the [Tooltip Not Found] action, not something you can do as part of the Attack action.
Remember when I said "usually" attacking with a weapon is done with the Attack action? Booming Blade is a spell that provides a different way to make an attack with a weapon. But that spell can't just be socketed in as one of your two Attack action attacks, it's its own action. And that action won't let you make a second attack, you'll only cast the spell once and make its one attack.
Same issue with Lorna's Shocking Grasp. It makes a melee spell attack, instead of a melee weapon attack, but again casting that spell is an entire action and not part of Attack and not something that your Extra Attack feature interacts with.
Don't think of spells as just being weapons, even spells that allow you to make a weapon attack or a spell attack as part of casting that spell are their own dedicated [Tooltip Not Found] action.
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I'm going to make this way harder than it needs to be.
The final thing I'll add is.... 9 out of 10 DMs will treat riding a mount the way that you've described, but it isn't quite right for the Steel Defender specifically. If you read closely... you'll notice that your Steel Defender doesn't actually share your turn, but rather has its own turn as an independent creature, immediately after your own:
That makes riding it around dynamically in battle.... almost impossible. You can certainly ride it! And you can command it where to move (which it will obey on its turn), and command it to attack (which it will obey on its turn). But attacking a target yourself, then commanding it to carry you off to a second target.... it won't be able to move during your turn.
But again, most DMs would probably be okay with you just merging your turn and your defender's turn together into a single mega-turn, because it feels bad and awkward for a rider to not be able to ride around on their own turn. In fact, riding in general allows you to control a mount on your own turn... so it's not clear if the Steel Defender HAS to keep its normal separate turn, or if you can instead choose to treat it like a controlled mount and merge it with your turn as normal. Presumably, treating it like a controlled mount would give you the benefit of it acting on your turn, but NOT override your ability to command it to take Steel Defender actions other than the limited Dash, Disengage, or Dodge menu that controlled mounts ordinarily have???
From PHB Chapter 9:
Similar issues for the Homunculus Servant. It can be ordered to move (which it will obey on its turn), or be ordered to take actions like Force strike (which it will obey on its turn), or you can cast spells through it on your own turn (which it uses its reaction on your turn to deliver), but you can't move it on your turn to get it into position to deliver a spell for you. Its fiddly, a lot of DMs ignore this for familiars and servants and again let the player just take one combined turn for both the PC and its pet.
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I'm going to make this way harder than it needs to be.
I would say that the Mount Rules you have listed would override the Steel Defender rules where they overlap if you are riding on the steel defender. That nerfs the SD if you want to control it as a mount, but only in the same way any other creature gets nerfed when you decide to ride on it.
That means that you could let it be independent, and use it as normal, but you can't make it move for you on your turn, or you can control it, and make it move for you on your turn, but give up it's other functions and abilities that aren't allowed for a controlled mount (like attacking). I'd make you choose when you mounted it, and not change it until you dismount it and remount it, or until combat ends and begins again.
Rather than cluttering up this thread with further mounted combat debate, I'm going to hop over into the Find Steed thread that someone just necro'd. :)
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I'm going to make this way harder than it needs to be.
Lorna doesn't need to don her Arcane Armor if it was light, because she can sleep in it. If it's medium or heavy, and it's probably heavy, needing to don her armor is exactly right. She does not need to crawl and should not crawl: she can stand up for 10 feet of movement, walk 15, and drop prone, rather than crawling 10. She'll still end up prone and hence be more protected from attacks from 10 or more feet away. That assumes a grid, because you said crawl 10, which only makes sense on a grid - if you're not on a grid the numbers change, including the crawl distance, but there's still no need to crawl.
C_C covered this, but to be clear, attack 1 resolves before attack 2. There are a wide variety of situations in which this matters.
This isn't actually a rule anywhere in the PHB, but is present as an optional rule that your DM may be using from Xanathar's Guide to Everything. Even before that book was published, however, it has always been such a common assumption for players and DMs, that its probably just good rules to live by.
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I'm going to make this way harder than it needs to be.
I think C_C covered all of the issues here, but I'll cover them too, just to be sure.
3 is too harsh. A character can hold a 2H weapon just fine while accessing material components or focuses (other than the difficulties drawing/stowing/dropping them using free object interactions). There’s no rule that every single component must be fondled simultaneously or suggesting that the attack needs to be made simultaneously with you touching your tool, bag, or crossbow. While holding hammer in one hand touch component/focus with the other to cast spell, let go of it and grip hammer with 2H while making attack completing the spell... that's a perfectly valid way to use Booming Blade.
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I'm going to make this way harder than it needs to be.
No, it's not too harsh, it's literally the reason normal casters invest in things like a ruby of the warmage. You have to have a free hand for your M components. The hammer gets a pass (it's already in a hand), but you need a free hand for the other one. Link is to the relevant rule.
Yes. And they have a free hand…. Hand 1 accesses a focus (tool or infused item). Hand 2 “brandishes” the hammer. Components, check, the spell is now “cast”! So now to resolve its effect, they put both hands on their hammer (at worst, dropping the tool/infused item if they were holding it, but all they really needed to do was fondle their worn haversack) and make an attack.
This is pretty garden variety casting here.
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I'm going to make this way harder than it needs to be.
Yea think I'll have to side with C_C here. The spell and the melee attack might be part of the same action but they are distinctly separate events. So holding the hammer with 1 hand during casting and 2 hands during the attack should be doable.
That's not how Artificers work, as I discussed in my post. Artificers modify their spells, as covered in the Artificer rules - for an Artificer, Booming Blade has two M components, only one of which is the weapon. If the weapon is an infusion, it can be both components at once.