I'm making a bladesinger wizard. I've been trying to figure out if it is a good idea to make it multiclass or not and what other class I should choose if I do so. If I choose to multiclass, I've been thinking of putting 3 levels into one of 2 classes. Fighter to get action surge, second wind, and dueling. I would pick one of 2 subclasses from fighter. Either battle master, so there's more stuff I can do with my bonus actions, or Eldritch Knight for more spells. The other class I was thinking of would be the Rogue, specifically the swashbuckler subclass. With the Rogue class I get dash and disengage as a bonus, sneak attack, and more versatility with weapon choices than what plain bladesinger has to offer. The swashbuckler subclass is what intrigued me as Fancy Footwork is exactly like the mobile feat minus 10 ft and the dash features as well as Rakish Audacity would allow me to use the sneak attack die in 1v1 combat which even though it's only an extra 2d6, that's still pretty good in my opinion. I'm leaning toward multi with rogue/swashbuckler but should I do something else instead?
The Extra Attacks given by Bladesinger is pretty darn good in conjunction with most melee classes. Swashbuckler is a good pick because you can run up to someone, Booming Blade them and then hit them again and then move away. Now if they pursue you they take the extra BB damage.
On the other hand if you go Fighter you essentially get an extra feat anyway depending on what levels you'll be playing. So you could grab Mobile and get the benefits of BM or EK. One other benefit of Fighter is to start with it to get CON save proficiency, which is nice for maintaining concentration.
I think you've identified some solid picks, it just depends on what you want to focus on.
If you want the most efficient 1 level dip for a Wizard you need to look no further than 1 level of Artificer. For the bargain basement price of 1 level you get: CON saves, more cantrips (Guidance is the biggie here), a bunch of 1st level spells you don't normally get access to (like Faerie Fire and Cure Wounds), access to medium armor and shields (which sadly you will not utilize as a Bladesinger) and you lose no spell slots from multiclassing nor do you lose any ASIs.
The only drawback is you lose the lvl 20 Wizard capstone and having your spell progression and extra attack delayed by 1 level.
EK does almost nothing for you as a Bladesinger, and its spell slot progression is so low as to not be worth it. Psi Warrior would make more sense, or Battle Smith to allow you to attack using Intelligence. The Psi Warrior provides a round-to-round damage increase that's probably as good or better than the sneak attack, since it has no limitations.
If your Charisma is actually high enough to make a Swashbuckler look interesting, then I'm assuming a Warlock MC is an option as well. The Genie gives you an interesting damage buff + other features, none of which rely on charisma modifier. The Talisman pact provides more non-Cha buffs to yourself, and the Protection of the Talisman invocation makes you quite good at concentration saves... as well as the new Eldritch Mind invocation, which can save you from having to take Warcaster. Warlock spells and cantrips can be focused on utility or defensive spells like Misty Step or whatever.
I'd say Psi Warrior or Battle Smith or Genie Talisman 'lock.
I would say that Battlesmith Artificer will be a great pick as well...no delay in slot progression and you can buff up your weapon in a lot of ways and be more SAD with the INT weapon attacks.
Also your steel defender makes your already super high AC even crazier with the reaction to create DIS on attacks against you.
My friend and I were discussing it, and Eldritch Knight + Bladesinger could be good if youre willing to take alot of levels in fighter. At 7th level, EKs get War Magic which says:
"Beginning at 7th level, when you use your action to cast a cantrip, you can make one weapon attack as a bonus action."
I'm not sure if theres an official ruling on how this interacts with the Bladesinger's Extra Attack, but one could argue that casting a cantrip as part of that Extra Attack would allow you to make a bonus action weapon attack as well. Thus you're bladesinger could make 2 weapon attacks and cast a cantrip on its turn.
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No delay in slot progression? 3/2 = 1.5 rounded up = 2. So a 3 level dip in Artificer will delay your slots by 1 level while delaying your spell casting progression as a Wizard by 3 levels.
My friend and I were discussing it, and Eldritch Knight + Bladesinger could be good if youre willing to take alot of levels in fighter. At 7th level, EKs get War Magic which says:
"Beginning at 7th level, when you use your action to cast a cantrip, you can make one weapon attack as a bonus action."
I'm not sure if theres an official ruling on how this interacts with the Bladesinger's Extra Attack, but one could argue that casting a cantrip as part of that Extra Attack would allow you to make a bonus action weapon attack as well. Thus you're bladesinger could make 2 weapon attacks and cast a cantrip on its turn.
No delay in slot progression? 3/2 = 1.5 rounded up = 2. So a 3 level dip in Artificer will delay your slots by 1 level while delaying your spell casting progression as a Wizard by 3 levels.
other half-casters (e.g. Paladin) are 1/2 casters/rounded down.
Artificers are 1/2 casters, round UP.
other full casters are 1/1.
Yeah this is why Artificers are weird.....they are really good dips for wizards most of the time due to the slot progression being the same. Funny enough bladesinger probably benefits the least from this as they have a good way of raising AC so the medium armor/shield you get with arty is less useful...but really useful for making a weapon INT based so you can SAD through most of the build.
By the end you are getting +11 to damage thanks to:
Base INT for Battlesmith Magic Weapon: +5
Enchanced weapon infusion: +1
Song of Victory: +5 from INT again
with a +12 to hit you are looking rather GISHY
You are correct though you would delay a bit with a 3 level dip but its not that bad overall. You could take it after bladesinger 6 to minimize the impact.
My friend and I were discussing it, and Eldritch Knight + Bladesinger could be good if youre willing to take alot of levels in fighter. At 7th level, EKs get War Magic which says:
"Beginning at 7th level, when you use your action to cast a cantrip, you can make one weapon attack as a bonus action."
I'm not sure if theres an official ruling on how this interacts with the Bladesinger's Extra Attack, but one could argue that casting a cantrip as part of that Extra Attack would allow you to make a bonus action weapon attack as well. Thus you're bladesinger could make 2 weapon attacks and cast a cantrip on its turn.
I can't stop thinking about this... EK 7/Bladesinger 6 certainly still leaves a healthy amount of room for further shennanigans...
One question to answer would be, does Bladesinger's unique Extra Attack mechanics stack with Figher's unique Extra Attack mechanics? I.E., if you're a Fighter 11/Bladesinger 6, can you attack three times per attack action and replace one attack with a cantrip? Or, do you have a choice between "Attack - Fighter" (three attacks) and "Attack - Wizard" (one attack & one cantrip)? I think you aren't allowed to merge them, since the multiclassing section provides "If you gain the Extra Attack class feature from more than one class, the features don't add together." That was written well before Bladesinger's unique Extra Attack was even a twinkle in anyone's eye, and at the time was talking about not adding multiple attacks together to get more than 2 unless a single class (Fighter) tells you to do so... but that isn't to say that authors didn't rely on it as intended when they later wrote a new Bladesinger version but used the old name.
So, assuming you can't be an EK 11/Bladesinger 6 and have an Action (Cantrip-Attack-Attack) + Bonus (Attack) rotation... there's still some other ways to squeeze in more attacks. We've Cruelty from the BH Mutant, but that takes 11 levels, no go.... we've got Ranger Gloomstalker, though that only applies in the first round of combat. We've got Haste, though it only provides one more physical Attack, not a second full Attack action, or an enhancement to the number of attacks within the Attack action. We've got Beast Barbarian's claw, but that will preclude the cantrip entirely. Samurai's Rapid Strike could provide another weapon attack within an attack action, but that obviously precludes being an EK, and is too high level to boot... same with Echo Knight's third level Unleash Incarnation. Am I missing another class feature that's within 7 levels, that we could tack on?
Really, EK still isn't doing much, if you remember that Bonus Action isn't really doing anything that Polearm Master or even just regular Two-Weapon Fighting would do. A Bloodhunter Mutant 11/Bladesinger with PAM or who dual wields would have no problems turning out 4 attacks in a round. A Monk/Bladesinger also would have no problems with 4 attacks in a round. Action Surge obviously is exciting, but actually better on those than it is on the EK (EK/Bladesinger does 5 attacks, Fighter 2/Bladesinger/Monk or Mutant does 7). A Sorcerer/Bladesinger would be able to pump out a quickened Bonus cantrip instead of a Bonus Attack, probably doing significantly more damage...
Once again, EK feels like it should be a thematic choice to merge with a gish... but there isn't actually as much synergy there as it first appears, the thing it says its good at (merging spells with melee attacks) is accomplished better by so many other classes!
My friend and I were discussing it, and Eldritch Knight + Bladesinger could be good if youre willing to take alot of levels in fighter. At 7th level, EKs get War Magic which says:
"Beginning at 7th level, when you use your action to cast a cantrip, you can make one weapon attack as a bonus action."
I'm not sure if theres an official ruling on how this interacts with the Bladesinger's Extra Attack, but one could argue that casting a cantrip as part of that Extra Attack would allow you to make a bonus action weapon attack as well. Thus you're bladesinger could make 2 weapon attacks and cast a cantrip on its turn.
I can't stop thinking about this... EK 7/Bladesinger 6 certainly still leaves a healthy amount of room for further shennanigans...
One question to answer would be, does Bladesinger's unique Extra Attack mechanics stack with Figher's unique Extra Attack mechanics? I.E., if you're a Fighter 11/Bladesinger 6, can you attack three times per attack action and replace one attack with a cantrip? Or, do you have a choice between "Attack - Fighter" (three attacks) and "Attack - Wizard" (one attack & one cantrip)? I think you aren't allowed to merge them, since the multiclassing section provides "If you gain the Extra Attack class feature from more than one class, the features don't add together." That was written well before Bladesinger's unique Extra Attack was even a twinkle in anyone's eye, and at the time was talking about not adding multiple attacks together to get more than 2 unless a single class (Fighter) tells you to do so... but that isn't to say that authors didn't rely on it as intended when they later wrote a new Bladesinger version but used the old name.
So, assuming you can't be an EK 11/Bladesinger 6 and have an Action (Cantrip-Attack-Attack) + Bonus (Attack) rotation... there's still some other ways to squeeze in more attacks. We've Cruelty from the BH Mutant, but that takes 11 levels, no go.... we've got Ranger Gloomstalker, though that only applies in the first round of combat. We've got Haste, though it only provides one more physical Attack, not a second full Attack action, or an enhancement to the number of attacks within the Attack action. We've got Beast Barbarian's claw, but that will preclude the cantrip entirely. Samurai's Rapid Strike could provide another weapon attack within an attack action, but that obviously precludes being an EK, and is too high level to boot... same with Echo Knight's third level Unleash Incarnation. Am I missing another class feature that's within 7 levels, that we could tack on?
Really, EK still isn't doing much, if you remember that Bonus Action isn't really doing anything that Polearm Master or even just regular Two-Weapon Fighting would do. A Bloodhunter Mutant 11/Bladesinger with PAM or who dual wields would have no problems turning out 4 attacks in a round. A Monk/Bladesinger also would have no problems with 4 attacks in a round. Action Surge obviously is exciting, but actually better on those than it is on the EK (EK/Bladesinger does 5 attacks, Fighter 2/Bladesinger/Monk or Mutant does 7). A Sorcerer/Bladesinger would be able to pump out a quickened Bonus cantrip instead of a Bonus Attack, probably doing significantly more damage...
Once again, EK feels like it should be a thematic choice to merge with a gish... but there isn't actually as much synergy there as it first appears, the thing it says its good at (merging spells with melee attacks) is accomplished better by so many other classes!
EK lvl 11 Extra attack will not stack with Bladesinger's Extra attack feature. I have been tinkering with a EK/Bladesinger build for a bit and the best split in my opinion is something along the lines of 7 EK/13 BS or 8 EK/12 BS. It comes down to whether you want an extra ASI vs access to lvl 7 spells and more spell slots.
I disagree, while the two features don‘t add into attack+attack+attack+cantrip, they do combine into attack+attack +(attack or cantrip). I don‘t see any rule or language that would prevent that. Fighter 11 gives you 2extra attacks and Bladesinger replaces one extra attack with a cantrip. Take a 17/3 Clerric/Paladin, while he doesn‘t gain an extra usage of channel divinity, he does gain more ways in how to use it. The same would apply here in my opinion, you don‘t gain more attacks, but more ways in how to use them. I would say though that it doesn’t stack with the EK feature, because the bonus attack only triggers when you use your action to cast a spell, while the cantrip for the Bladesinger is part of the Attack action.
Also, we are talking about a lvl 17 character here, a cantrip plus two attacks won‘t break the game any more then a Meteor Swarm or a Wish at that point.
I disagree, while the two features don‘t add into attack+attack+attack+cantrip, they do combine into attack+attack +(attack or cantrip). I don‘t see any rule or language that would prevent that. Fighter 11 gives you 2extra attacks and Bladesinger replaces one extra attack with a cantrip. Take a 17/3 Clerric/Paladin, while he doesn‘t gain an extra usage of channel divinity, he does gain more ways in how to use it. The same would apply here in my opinion, you don‘t gain more attacks, but more ways in how to use them. I would say though that it doesn’t stack with the EK feature, because the bonus attack only triggers when you use your action to cast a spell, while the cantrip for the Bladesinger is part of the Attack action.
Also, we are talking about a lvl 17 character here, a cantrip plus two attacks won‘t break the game any more then a Meteor Swarm or a Wish at that point.
I would like to draw your attention to the pg 164 of the PHB
Extra Attack
If you gain the Extra Attack class feature from more than one class, the features don't add together. You can't make more than two attacks with this feature unless it says you do (as the fighter's version of Extra Attack does). Similarly, the warlock's eldritch invocation Thirsting Blade doesn't give you additional attacks if you also have Extra Attack.
Since the features do not add together you have to use one or the other. In order to use 3 attacks you obviously have to use the Fighter's Extra Attack feature and not the Bladesinger's. And it is the Bladesinger's Extra Attack feature that allows you to replace an attack with a cantrip.
Also your example of Channel Divinity is covered on the same page which reads:
Channel Divinity
If you already have the Channel Divinity feature and gain a level in a class that also grants the feature, you gain the Channel Divinity effects granted by that class, but getting the feature again doesn't give you an additional use of it. You gain additional uses only when you reach a class level that explicitly grants them to you. For example, if you are a cleric 6/paladin 4, you can use Channel Divinity twice between rests because you are high enough level in the cleric class to have more uses. Whenever you use the feature, you can choose any of the Channel Divinity effects available to you from your two classes.
So your 17cleric/3 paladin can use the paladin channel divinity 2 times between rests because that is the higher cap allowed by the 17 levels of cleric as it is written in the rules.
I would like to draw your attention to the pg 164 of the PHB
Extra Attack
If you gain the Extra Attack class feature from more than one class, the features don't add together. You can't make more than two attacks with this feature unless it says you do (as the fighter's version of Extra Attack does). Similarly, the warlock's eldritch invocation Thirsting Blade doesn't give you additional attacks if you also have Extra Attack.
Since the features do not add together you have to use one or the other. In order to use 3 attacks you obviously have to use the Fighter's Extra Attack feature and not the Bladesinger's. And it is the Bladesinger's Extra Attack feature that allows you to replace an attack with a cantrip.
Bladesinger:
Extra Attack
6th-level Bladesinging feature
You can attack twice, instead of once, whenever you take the Attack action on your turn. Moreover, you can cast one of your cantrips in place of one of those attacks.
I am not saying that they add, but that they combine. You still only got three attacks as per Fighter lvl 11 feature, but one of those three can be a cantrip as per Bladesinger feature.
That's the problem I have with your argument. You admit that Extra Attack features cannot stack but somehow you can cherry pick bits and pieces from 2 different Extra Attack features. The cantrip replacement is a PART of the Bladesinger's Extra Attack Feature much like Attacking 3 times is a PART of the Fighter's level 11 Extra Attack Feature. You cannot just take bits of one and bits of another and then claim you are not adding the features together.
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I'm making a bladesinger wizard. I've been trying to figure out if it is a good idea to make it multiclass or not and what other class I should choose if I do so. If I choose to multiclass, I've been thinking of putting 3 levels into one of 2 classes. Fighter to get action surge, second wind, and dueling. I would pick one of 2 subclasses from fighter. Either battle master, so there's more stuff I can do with my bonus actions, or Eldritch Knight for more spells. The other class I was thinking of would be the Rogue, specifically the swashbuckler subclass. With the Rogue class I get dash and disengage as a bonus, sneak attack, and more versatility with weapon choices than what plain bladesinger has to offer. The swashbuckler subclass is what intrigued me as Fancy Footwork is exactly like the mobile feat minus 10 ft and the dash features as well as Rakish Audacity would allow me to use the sneak attack die in 1v1 combat which even though it's only an extra 2d6, that's still pretty good in my opinion. I'm leaning toward multi with rogue/swashbuckler but should I do something else instead?
The Extra Attacks given by Bladesinger is pretty darn good in conjunction with most melee classes. Swashbuckler is a good pick because you can run up to someone, Booming Blade them and then hit them again and then move away. Now if they pursue you they take the extra BB damage.
On the other hand if you go Fighter you essentially get an extra feat anyway depending on what levels you'll be playing. So you could grab Mobile and get the benefits of BM or EK. One other benefit of Fighter is to start with it to get CON save proficiency, which is nice for maintaining concentration.
I think you've identified some solid picks, it just depends on what you want to focus on.
My homebrew subclasses (full list here)
(Artificer) Swordmage | Glasswright | (Barbarian) Path of the Savage Embrace
(Bard) College of Dance | (Fighter) Warlord | Cannoneer
(Monk) Way of the Elements | (Ranger) Blade Dancer
(Rogue) DaggerMaster | Inquisitor | (Sorcerer) Riftwalker | Spellfist
(Warlock) The Swarm
How about Bard? You gain spell slots, and Flourishes add even more damage and defence to your build.
Attack: [roll]3d20dl2+6[/roll] Damage: [roll](if([roll:-1:critical], =0, 1d8, 2{1d8}.expand()))+4[/roll] Sneakattack: [roll](if([roll:-2:critical], =0, 2d6, 2{2d6}.expand()))[/roll]If you want the most efficient 1 level dip for a Wizard you need to look no further than 1 level of Artificer. For the bargain basement price of 1 level you get: CON saves, more cantrips (Guidance is the biggie here), a bunch of 1st level spells you don't normally get access to (like Faerie Fire and Cure Wounds), access to medium armor and shields (which sadly you will not utilize as a Bladesinger) and you lose no spell slots from multiclassing nor do you lose any ASIs.
The only drawback is you lose the lvl 20 Wizard capstone and having your spell progression and extra attack delayed by 1 level.
EK does almost nothing for you as a Bladesinger, and its spell slot progression is so low as to not be worth it. Psi Warrior would make more sense, or Battle Smith to allow you to attack using Intelligence. The Psi Warrior provides a round-to-round damage increase that's probably as good or better than the sneak attack, since it has no limitations.
If your Charisma is actually high enough to make a Swashbuckler look interesting, then I'm assuming a Warlock MC is an option as well. The Genie gives you an interesting damage buff + other features, none of which rely on charisma modifier. The Talisman pact provides more non-Cha buffs to yourself, and the Protection of the Talisman invocation makes you quite good at concentration saves... as well as the new Eldritch Mind invocation, which can save you from having to take Warcaster. Warlock spells and cantrips can be focused on utility or defensive spells like Misty Step or whatever.
I'd say Psi Warrior or Battle Smith or Genie Talisman 'lock.
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I would say that Battlesmith Artificer will be a great pick as well...no delay in slot progression and you can buff up your weapon in a lot of ways and be more SAD with the INT weapon attacks.
Also your steel defender makes your already super high AC even crazier with the reaction to create DIS on attacks against you.
My build for Arty 3/ Bladesinger 17: https://ddb.ac/characters/45333406/aPAebx
My friend and I were discussing it, and Eldritch Knight + Bladesinger could be good if youre willing to take alot of levels in fighter. At 7th level, EKs get War Magic which says:
"Beginning at 7th level, when you use your action to cast a cantrip, you can make one weapon attack as a bonus action."
I'm not sure if theres an official ruling on how this interacts with the Bladesinger's Extra Attack, but one could argue that casting a cantrip as part of that Extra Attack would allow you to make a bonus action weapon attack as well. Thus you're bladesinger could make 2 weapon attacks and cast a cantrip on its turn.
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No delay in slot progression? 3/2 = 1.5 rounded up = 2. So a 3 level dip in Artificer will delay your slots by 1 level while delaying your spell casting progression as a Wizard by 3 levels.
EKS are 1/3 casters, round down.
other half-casters (e.g. Paladin) are 1/2 casters/rounded down.
Artificers are 1/2 casters, round UP.
other full casters are 1/1.
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I'm going to make this way harder than it needs to be.
That’s.... actually pretty defensible. Good idea!
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I'm going to make this way harder than it needs to be.
Yeah this is why Artificers are weird.....they are really good dips for wizards most of the time due to the slot progression being the same. Funny enough bladesinger probably benefits the least from this as they have a good way of raising AC so the medium armor/shield you get with arty is less useful...but really useful for making a weapon INT based so you can SAD through most of the build.
By the end you are getting +11 to damage thanks to:
Base INT for Battlesmith Magic Weapon: +5
Enchanced weapon infusion: +1
Song of Victory: +5 from INT again
with a +12 to hit you are looking rather GISHY
You are correct though you would delay a bit with a 3 level dip but its not that bad overall. You could take it after bladesinger 6 to minimize the impact.
I can't stop thinking about this... EK 7/Bladesinger 6 certainly still leaves a healthy amount of room for further shennanigans...
One question to answer would be, does Bladesinger's unique Extra Attack mechanics stack with Figher's unique Extra Attack mechanics? I.E., if you're a Fighter 11/Bladesinger 6, can you attack three times per attack action and replace one attack with a cantrip? Or, do you have a choice between "Attack - Fighter" (three attacks) and "Attack - Wizard" (one attack & one cantrip)? I think you aren't allowed to merge them, since the multiclassing section provides "If you gain the Extra Attack class feature from more than one class, the features don't add together." That was written well before Bladesinger's unique Extra Attack was even a twinkle in anyone's eye, and at the time was talking about not adding multiple attacks together to get more than 2 unless a single class (Fighter) tells you to do so... but that isn't to say that authors didn't rely on it as intended when they later wrote a new Bladesinger version but used the old name.
So, assuming you can't be an EK 11/Bladesinger 6 and have an Action (Cantrip-Attack-Attack) + Bonus (Attack) rotation... there's still some other ways to squeeze in more attacks. We've Cruelty from the BH Mutant, but that takes 11 levels, no go.... we've got Ranger Gloomstalker, though that only applies in the first round of combat. We've got Haste, though it only provides one more physical Attack, not a second full Attack action, or an enhancement to the number of attacks within the Attack action. We've got Beast Barbarian's claw, but that will preclude the cantrip entirely. Samurai's Rapid Strike could provide another weapon attack within an attack action, but that obviously precludes being an EK, and is too high level to boot... same with Echo Knight's third level Unleash Incarnation. Am I missing another class feature that's within 7 levels, that we could tack on?
Really, EK still isn't doing much, if you remember that Bonus Action isn't really doing anything that Polearm Master or even just regular Two-Weapon Fighting would do. A Bloodhunter Mutant 11/Bladesinger with PAM or who dual wields would have no problems turning out 4 attacks in a round. A Monk/Bladesinger also would have no problems with 4 attacks in a round. Action Surge obviously is exciting, but actually better on those than it is on the EK (EK/Bladesinger does 5 attacks, Fighter 2/Bladesinger/Monk or Mutant does 7). A Sorcerer/Bladesinger would be able to pump out a quickened Bonus cantrip instead of a Bonus Attack, probably doing significantly more damage...
Once again, EK feels like it should be a thematic choice to merge with a gish... but there isn't actually as much synergy there as it first appears, the thing it says its good at (merging spells with melee attacks) is accomplished better by so many other classes!
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EK lvl 11 Extra attack will not stack with Bladesinger's Extra attack feature. I have been tinkering with a EK/Bladesinger build for a bit and the best split in my opinion is something along the lines of 7 EK/13 BS or 8 EK/12 BS. It comes down to whether you want an extra ASI vs access to lvl 7 spells and more spell slots.
I disagree, while the two features don‘t add into attack+attack+attack+cantrip, they do combine into attack+attack +(attack or cantrip). I don‘t see any rule or language that would prevent that. Fighter 11 gives you 2extra attacks and Bladesinger replaces one extra attack with a cantrip.
Take a 17/3 Clerric/Paladin, while he doesn‘t gain an extra usage of channel divinity, he does gain more ways in how to use it. The same would apply here in my opinion, you don‘t gain more attacks, but more ways in how to use them.
I would say though that it doesn’t stack with the EK feature, because the bonus attack only triggers when you use your action to cast a spell, while the cantrip for the Bladesinger is part of the Attack action.
Also, we are talking about a lvl 17 character here, a cantrip plus two attacks won‘t break the game any more then a Meteor Swarm or a Wish at that point.
Attack: [roll]3d20dl2+6[/roll] Damage: [roll](if([roll:-1:critical], =0, 1d8, 2{1d8}.expand()))+4[/roll] Sneakattack: [roll](if([roll:-2:critical], =0, 2d6, 2{2d6}.expand()))[/roll]I would like to draw your attention to the pg 164 of the PHB
Extra Attack
If you gain the Extra Attack class feature from more than one class, the features don't add together. You can't make more than two attacks with this feature unless it says you do (as the fighter's version of Extra Attack does). Similarly, the warlock's eldritch invocation Thirsting Blade doesn't give you additional attacks if you also have Extra Attack.
Since the features do not add together you have to use one or the other. In order to use 3 attacks you obviously have to use the Fighter's Extra Attack feature and not the Bladesinger's. And it is the Bladesinger's Extra Attack feature that allows you to replace an attack with a cantrip.
Also your example of Channel Divinity is covered on the same page which reads:
Channel Divinity
If you already have the Channel Divinity feature and gain a level in a class that also grants the feature, you gain the Channel Divinity effects granted by that class, but getting the feature again doesn't give you an additional use of it. You gain additional uses only when you reach a class level that explicitly grants them to you. For example, if you are a cleric 6/paladin 4, you can use Channel Divinity twice between rests because you are high enough level in the cleric class to have more uses. Whenever you use the feature, you can choose any of the Channel Divinity effects available to you from your two classes.
So your 17cleric/3 paladin can use the paladin channel divinity 2 times between rests because that is the higher cap allowed by the 17 levels of cleric as it is written in the rules.
You either get 3 attacks or 2 with one being a cantrip is how I think it works.
Bladesinger:
I am not saying that they add, but that they combine. You still only got three attacks as per Fighter lvl 11 feature, but one of those three can be a cantrip as per Bladesinger feature.
Attack: [roll]3d20dl2+6[/roll] Damage: [roll](if([roll:-1:critical], =0, 1d8, 2{1d8}.expand()))+4[/roll] Sneakattack: [roll](if([roll:-2:critical], =0, 2d6, 2{2d6}.expand()))[/roll]That's the problem I have with your argument. You admit that Extra Attack features cannot stack but somehow you can cherry pick bits and pieces from 2 different Extra Attack features. The cantrip replacement is a PART of the Bladesinger's Extra Attack Feature much like Attacking 3 times is a PART of the Fighter's level 11 Extra Attack Feature. You cannot just take bits of one and bits of another and then claim you are not adding the features together.