If you have Gaze of Two Minds active on your ally, call them X.
1/ If you cast a cantrip like booming blade, can you make a melee attack against a target adjacent to X? (Because the "within 5' " overrides the weapon's reach, and the attack is part of the spell?) True Strike? (Doesn't have the 5' range specification, but the attack is still part of the spell? -- I'm thinking the lack of the range specification is key) If yes with True Strike, what about True Strike with a ranged weapon - would the ammunition fire from X's position?
Best guess: Yes (booming), no, no
If you're a Warlock/Rogue multiclass and at least one of the melee options works, do you get sneak attack dice? (Because X is adjacent to them?) Best Guess: yes.
2/ If you're invisible from hiding and cast a spell (without verbal components) with an attack roll originating from X's position, do you lose invisibility because of the attack roll? More interested in RAI here / logic of what the rules are intending to represent. (RAW is obviously yes, but it's silly.)
3/ Even when not unseen or invisible, should you get advantage when casting a spell with an attack roll from X's position? (because they see/hear you casting the spell, but then the spell originates from somewhere else?) Only the first time? (unless you change who you're 'gazing' through?)
4/ If X is unseen/invisible, but you're visibly casting a spell with an attack roll, do you gain advantage when it originates from X's position? Does it affect X's invisibility? (I'd think no on the latter).
5/ If the enemy cannot perceive you casting the spell, they can't counterspell it when it originates from X, right? Because X isn't spellcasting?
1. No. These spells enable you to make a weapon attack. Gaze of the Two Minds does not allow you to make weapon attacks from a second location.
2. Making an attack roll drops Stealth. Gaze of the Two Minds doesn't change this.
3. No. If the ability gave you advantage, it would say it gives you advantage.
4. No. You gain advantage when you're Invisible. Your ally's visibility isn't relevant, nor would it be affected by your spellcasting.
5. If the enemy can't see you casting the spell, they can't counterspell it. Gaze of Two Minds doesn't affect this except in the sense that it's a bit easier to set up situations where you're casting around a corner because you can see them but they can't see you.
1/ If you cast a cantrip like booming blade, can you make a melee attack against a target adjacent to X? (Because the "within 5' " overrides the weapon's reach, and the attack is part of the spell?) True Strike? (Doesn't have the 5' range specification, but the attack is still part of the spell? -- I'm thinking the lack of the range specification is key) If yes with True Strike, what about True Strike with a ranged weapon - would the ammunition fire from X's position?
The main problem here is "you make one attack with the weapon used in the spell’s casting", and your ally X isn't wielding that weapon.
2/ If you're invisible from hiding and cast a spell (without verbal components) with an attack roll originating from X's position, do you lose invisibility because of the attack roll? More interested in RAI here / logic of what the rules are intending to represent. (RAW is obviously yes, but it's silly.)
Yes, because you as the caster is making the attack:
You stop being hidden immediately after any of the following occurs: you make a sound louder than a whisper, an enemy finds you, you make an attack roll, or you cast a spell with a Verbal component.
3/ Even when not unseen or invisible, should you get advantage when casting a spell with an attack roll from X's position? (because they see/hear you casting the spell, but then the spell originates from somewhere else?) Only the first time? (unless you change who you're 'gazing' through?)
No, you would have Advantage, for example, in your previous example, because you had the Invisible condition.
4/ If X is unseen/invisible, but you're visibly casting a spell with an attack roll, do you gain advantage when it originates from X's position? Does it affect X's invisibility? (I'd think no on the latter).
This is the opposite of your second scenario, so no, because you as the caster are the one making the attack.
5/ If the enemy cannot perceive you casting the spell, they can't counterspell it when it originates from X, right? Because X isn't spellcasting?
No, because you're casting the spell, not your ally X, and Counterspell says:
Casting Time: Reaction, which you take when you see a creature within 60 feet of yourselfcasting a spellwith Verbal, Somatic, or Material components
1. No. These spells enable you to make a weapon attack. Gaze of the Two Minds does not allow you to make weapon attacks from a second location.
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'. Basically, it replaces the range of the weapon with the 'within 5' of you' range (ie, you can't make an attack 10' away with reach either, because the spell has replaced your attack range). So you make a melee attack within 5' of them. There are other instances of melee attacks not in normal melee range (Steel Wind Strike), so it being a melee attack wouldn't seem to prevent that from happening.
2. Making an attack roll drops Stealth. Gaze of the Two Minds doesn't change this.
Which is why I asked for RAI. Normally you drop stealth because they can tell where the attack came from, but with Gaze, the attack didn't come from you. So yes, technically RAW it still ends hiding's invisibility, but should it?
Actually, a lot of these are instances where the RAW makes me go 'that sounds weird, what's the internal logic here?'.
Steel Wind Strike only uses the weapon as a material component. It doesn't attack with the weapon or use any of its characteristics - it's a pure spell attack like Fireball.
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'.
No, it doesn't. You don't get to just change the text of spells like that
You're casting the spell from the other creature's space, sure. You're still the one wielding the weapon, and the target still has to be within 5 feet of you
Contrast that with the wording for Steel Wind Strike
You flourish the weapon used in the casting and then vanish to strike like the wind. Choose up to five creatures you can see within range. Make a melee spell attack against each target. On a hit, a target takes 6d10 Force damage.
You then teleport to an unoccupied space you can see within 5 feet of one of the targets.
There, the targets only have to be within the spell's range, and it specifically involves teleporting to them. However, you would still be the one who teleports to an unoccupied space within 5 feet of one of the targets -- not the creature you were using Go2M on
Rollback Post to RevisionRollBack
Active characters:
Edoumiaond Willegume "Eddie" Podslee, Vegetanian scholar (College of Spirits bard) Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric) Mardan Ferres, elven private investigator (Assassin rogue) Peter "the Pied Piper" Hausler, human con artist/remover of vermin (Circle of the Shepherd druid) Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'.
No, it doesn't. You don't get to just change the text of spells like that
You're casting the spell from the other creature's space, sure. You're still the one wielding the weapon, and the target still has to be within 5 feet of you
Contrast that with the wording for Steel Wind Strike
You flourish the weapon used in the casting and then vanish to strike like the wind. Choose up to five creatures you can see within range. Make a melee spell attack against each target. On a hit, a target takes 6d10 Force damage.
You then teleport to an unoccupied space you can see within 5 feet of one of the targets.
There, the targets only have to be within the spell's range, and it specifically involves teleporting to them. However, you would still be the one who teleports to an unoccupied space within 5 feet of one of the targets -- not the creature you were using Go2M on
So you're saying you still measure the spell's range from you? I'm pretty sure you measure the range from your ally X.
You cast the spell as if you were in your ally's space, meaning within 5' of you is within 5' of their space, because you're treating yourself as being located there.
Steel Wind Strike only uses the weapon as a material component. It doesn't attack with the weapon or use any of its characteristics - it's a pure spell attack like Fireball.
Booming Blade also uses the weapon as a material component. That you use the weapon's damage die is not a material difference (pun intended).
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'.
No, it doesn't. You don't get to just change the text of spells like that
You're casting the spell from the other creature's space, sure. You're still the one wielding the weapon, and the target still has to be within 5 feet of you
Contrast that with the wording for Steel Wind Strike
You flourish the weapon used in the casting and then vanish to strike like the wind. Choose up to five creatures you can see within range. Make a melee spell attack against each target. On a hit, a target takes 6d10 Force damage.
You then teleport to an unoccupied space you can see within 5 feet of one of the targets.
There, the targets only have to be within the spell's range, and it specifically involves teleporting to them. However, you would still be the one who teleports to an unoccupied space within 5 feet of one of the targets -- not the creature you were using Go2M on
So you're saying you still measure the spell's range from you?
Did I say that? No
Since you seem more interested in starting arguments than in understanding why your interpretation isn't RAW, I'll bow out here
Rollback Post to RevisionRollBack
Active characters:
Edoumiaond Willegume "Eddie" Podslee, Vegetanian scholar (College of Spirits bard) Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric) Mardan Ferres, elven private investigator (Assassin rogue) Peter "the Pied Piper" Hausler, human con artist/remover of vermin (Circle of the Shepherd druid) Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'.
No, it doesn't. You don't get to just change the text of spells like that
You're casting the spell from the other creature's space, sure. You're still the one wielding the weapon, and the target still has to be within 5 feet of you
Contrast that with the wording for Steel Wind Strike
You flourish the weapon used in the casting and then vanish to strike like the wind. Choose up to five creatures you can see within range. Make a melee spell attack against each target. On a hit, a target takes 6d10 Force damage.
You then teleport to an unoccupied space you can see within 5 feet of one of the targets.
There, the targets only have to be within the spell's range, and it specifically involves teleporting to them. However, you would still be the one who teleports to an unoccupied space within 5 feet of one of the targets -- not the creature you were using Go2M on
So you're saying you still measure the spell's range from you?
Did I say that? No
Since you seem more interested in starting arguments than in understanding why your interpretation isn't RAW, I'll bow out here
You did say that right here: "You're still the one wielding the weapon, and the target still has to be within 5 feet of you". The range of the spell is 5', so you're saying you're measuring the range from you (rather than the Gaze target). And that's why I find your explanation unconvincing, since you're measuring spell range improperly.
I didn't change the text of the spell. I'm just relying on the caster counting as where his Gaze ally is for the purposes of the spell, and thus measures the 5' range of the spell from there. That its a melee attack is irrelevant, so long as they're within 5' of where you count as being, they're a valid target I'd think. (I am willing to agree with you that, because True Strike lacks the range wording, True Strike cannot work this way).
Yes, my reading means that you get to make a melee attack within 5' of where you count as being with a weapon you're holding up to 60' away from there. But that's a consequence of the wording of the spell.
(My point about Steel Wind Strike was that you were making melee attacks while outside normal melee range, so you can make melee attacks from farther away when the rules tell you to do so. Yes, I agree, you're the one who teleports if you use Gaze to cast Steel Wind Strike, but you measure the 30' range from the Gaze target, so you could potentially hit targets 90' away from you (assuming you were 60' behind the gaze target relative to them), and teleport up to 95' afterwards (if you struck someone 30' from the Gaze target, who was 60' from you, and then teleported behind them. Possibly farther than 95' if they're bigger than medium size. You could even cast Steel Wind Strike from the other side of a wall with Gaze, and somehow hit someone 90' away from you while still behind the wall, with a melee attack - you only teleport after you hit).
------------------------------
Thought experiment: You have a gaze target 10' from you. An enemy adjacent to him is also 10' from you. You cast booming blade and use a reach weapon as the material component. Are you allowed to hit that enemy? Why or why not? What if they're 15' from you? Why or why not?
(Follow-up: Doesn't the 5' range of the spell replace the reach of the weapon? ie, if not for Gaze, can we all agree I can't attack an enemy 10' from me with Booming Blade, even if I'm using a weapon with reach?)
1) No. Because the weapon is used to strike instead of just the spell, and the weapon doesn't move through the space between you, you can't do this. You're limited by the weapon's location.
2) Reminder that D&D isn't a reality simulator, but hiding often requires holding still and somatic casting still cause rustling/rattling of your gear. That said, yes you lose the invisible condition, but you might still be fully obscured if you have a physical obstruction between yourself and all others.
3) Not at all. If you have the Invisible condition to indicate you've hidden successfully, your first attack will be at advantage. Otherwise, there's no reason that a spell coming from another spot when they're aware of casting happening should be that big of a deal.
4) No and no. No matter what, you are still the origin of the spell. However, while they don't lose their invisibility, it's possible that this could reveal their general presence depending on the spell. (This would depend on how the spell manifests. Scorching Ray should show their general area because it visibly flies from that space. Hold Person likely wouldn't, as an example, because it isn't a glaringly obvious series of fire shots.)
5) They cannot. Not only that, but Counterspell is one of the biggest advantages you have, as you can treat yourself as being in the other space and counter them even while you're out of range.
but hiding often requires holding still and somatic casting still cause rustling/rattling of your gear
This is not RAW nor likely even RAI. Hiding's invisibility specifically and only says a spell with verbal components breaks your invisibility, so only verbal component spells break it. You can cast S and M spells while hiding without breaking invisibility just fine.
(Contrast with spell invisibility, where casting any spell causes you to break it).
Rustling clothing or gear would be the result of a bad stealth roll (and if that was going to cause your hide to fail, it would have failed the moment they got to test your stealth with perception, passive or otherwise, not when you went to cast a spell. Once hiding, you keep that stealth result until you stop hiding).
but hiding often requires holding still and somatic casting still cause rustling/rattling of your gear
This is not RAW nor likely even RAI. Hiding's invisibility specifically and only says a spell with verbal components breaks your invisibility, so only verbal component spells break it. You can cast S and M spells while hiding without breaking invisibility just fine.
(Contrast with spell invisibility, where casting any spell causes you to break it).
Rustling clothing or gear would be the result of a bad stealth roll (and if that was going to cause your hide to fail, it would have failed the moment they got to test your stealth with perception, passive or otherwise, not when you went to cast a spell. Once hiding, you keep that stealth result until you stop hiding).
You asked. You know the RAW of the spells in question (those which require an attack roll) reveals you even without verbal components. Will creatures necessarily know where you are? That depends on the situation and the ruling made by the DM at the time. But I was just giving an example of how it could be justified. Don't ask for what logic could justify the rule if you're just going to argue over a person's thoughts on the matter.
Also remember: D&D isn't, nor should it ever be, a real-world simulator. It's a game with rules that exist to keep things flowing. Any deviation from the rules should be an agreement you and your DM (and table) make, not you just pushing for a result.
(Follow-up: Doesn't the 5' range of the spell replace the reach of the weapon?
No, Range and Reach are separate concepts. Usually Reach is the only one that is relevant for melee weapon attacks but due to the text of the spell the "within 5 feet" is also relevant for this attack, so you need to abide by both.
I didn't change the text of the spell. I'm just relying on the caster counting as where his Gaze ally is for the purposes of the spell, and thus measures the 5' range of the spell from there. That its a melee attack is irrelevant, so long as they're within 5' of where you count as being, they're a valid target I'd think. (I am willing to agree with you that, because True Strike lacks the range wording, True Strike cannot work this way).
Yes, my reading means that you get to make a melee attack within 5' of where you count as being with a weapon you're holding up to 60' away from there. But that's a consequence of the wording of the spell.
No the fact that it is a melee weapon attack is very relevant. So you can cast the spell and the target then has to be within 5 feet (measured from Ally X) but for you to be able to hit it it also needs to be within your reach with the weapon (measured from you).
Booming Blade also uses the weapon as a material component. That you use the weapon's damage die is not a material difference (pun intended).
You really shouldn't misrepresent the rules like that. When you cast Booming Blade you are making a weapon attack with the weapon in addition to using it as the material component but when you cast Steel Wind Strike you are making a spell attack while only using the weapon as the material component. Weapon attacks and spell attacks are not the same and that does make for a material difference here.
If you have Gaze of Two Minds active on your ally, call them X.
1/ If you cast a cantrip like booming blade, can you make a melee attack against a target adjacent to X? (Because the "within 5' " overrides the weapon's reach, and the attack is part of the spell?) True Strike? (Doesn't have the 5' range specification, but the attack is still part of the spell? -- I'm thinking the lack of the range specification is key) If yes with True Strike, what about True Strike with a ranged weapon - would the ammunition fire from X's position?
Best guess: Yes (booming), no, no
If you're a Warlock/Rogue multiclass and at least one of the melee options works, do you get sneak attack dice? (Because X is adjacent to them?) Best Guess: yes.
2/ If you're invisible from hiding and cast a spell (without verbal components) with an attack roll originating from X's position, do you lose invisibility because of the attack roll? More interested in RAI here / logic of what the rules are intending to represent. (RAW is obviously yes, but it's silly.)
3/ Even when not unseen or invisible, should you get advantage when casting a spell with an attack roll from X's position? (because they see/hear you casting the spell, but then the spell originates from somewhere else?) Only the first time? (unless you change who you're 'gazing' through?)
4/ If X is unseen/invisible, but you're visibly casting a spell with an attack roll, do you gain advantage when it originates from X's position? Does it affect X's invisibility? (I'd think no on the latter).
5/ If the enemy cannot perceive you casting the spell, they can't counterspell it when it originates from X, right? Because X isn't spellcasting?
1. No. These spells enable you to make a weapon attack. Gaze of the Two Minds does not allow you to make weapon attacks from a second location.
2. Making an attack roll drops Stealth. Gaze of the Two Minds doesn't change this.
3. No. If the ability gave you advantage, it would say it gives you advantage.
4. No. You gain advantage when you're Invisible. Your ally's visibility isn't relevant, nor would it be affected by your spellcasting.
5. If the enemy can't see you casting the spell, they can't counterspell it. Gaze of Two Minds doesn't affect this except in the sense that it's a bit easier to set up situations where you're casting around a corner because you can see them but they can't see you.
The main problem here is "you make one attack with the weapon used in the spell’s casting", and your ally X isn't wielding that weapon.
Yes, because you as the caster is making the attack:
No, you would have Advantage, for example, in your previous example, because you had the Invisible condition.
This is the opposite of your second scenario, so no, because you as the caster are the one making the attack.
No, because you're casting the spell, not your ally X, and Counterspell says:
If you're interested, I asked similar questions to 2–4 here: Gaze of Two Minds 2024 -- multiple senses at once?
EDIT: fix tooltip.
Are you sure? Booming Blade (first sentence): "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." The melee attack is part of the spell, and Gaze lets you cast the spell from X's location, so it becomes 'within 5' of your ally, X'. Basically, it replaces the range of the weapon with the 'within 5' of you' range (ie, you can't make an attack 10' away with reach either, because the spell has replaced your attack range). So you make a melee attack within 5' of them. There are other instances of melee attacks not in normal melee range (Steel Wind Strike), so it being a melee attack wouldn't seem to prevent that from happening.
Which is why I asked for RAI. Normally you drop stealth because they can tell where the attack came from, but with Gaze, the attack didn't come from you. So yes, technically RAW it still ends hiding's invisibility, but should it?
Actually, a lot of these are instances where the RAW makes me go 'that sounds weird, what's the internal logic here?'.
Steel Wind Strike only uses the weapon as a material component. It doesn't attack with the weapon or use any of its characteristics - it's a pure spell attack like Fireball.
No, it doesn't. You don't get to just change the text of spells like that
You're casting the spell from the other creature's space, sure. You're still the one wielding the weapon, and the target still has to be within 5 feet of you
Contrast that with the wording for Steel Wind Strike
There, the targets only have to be within the spell's range, and it specifically involves teleporting to them. However, you would still be the one who teleports to an unoccupied space within 5 feet of one of the targets -- not the creature you were using Go2M on
Active characters:
Edoumiaond Willegume "Eddie" Podslee, Vegetanian scholar (College of Spirits bard)
Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric)
Mardan Ferres, elven private investigator (Assassin rogue)
Peter "the Pied Piper" Hausler, human con artist/remover of vermin (Circle of the Shepherd druid)
Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
So you're saying you still measure the spell's range from you? I'm pretty sure you measure the range from your ally X.
You cast the spell as if you were in your ally's space, meaning within 5' of you is within 5' of their space, because you're treating yourself as being located there.
Booming Blade also uses the weapon as a material component. That you use the weapon's damage die is not a material difference (pun intended).
Did I say that? No
Since you seem more interested in starting arguments than in understanding why your interpretation isn't RAW, I'll bow out here
Active characters:
Edoumiaond Willegume "Eddie" Podslee, Vegetanian scholar (College of Spirits bard)
Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric)
Mardan Ferres, elven private investigator (Assassin rogue)
Peter "the Pied Piper" Hausler, human con artist/remover of vermin (Circle of the Shepherd druid)
Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
You did say that right here: "You're still the one wielding the weapon, and the target still has to be within 5 feet of you". The range of the spell is 5', so you're saying you're measuring the range from you (rather than the Gaze target). And that's why I find your explanation unconvincing, since you're measuring spell range improperly.
I didn't change the text of the spell. I'm just relying on the caster counting as where his Gaze ally is for the purposes of the spell, and thus measures the 5' range of the spell from there. That its a melee attack is irrelevant, so long as they're within 5' of where you count as being, they're a valid target I'd think. (I am willing to agree with you that, because True Strike lacks the range wording, True Strike cannot work this way).
Yes, my reading means that you get to make a melee attack within 5' of where you count as being with a weapon you're holding up to 60' away from there. But that's a consequence of the wording of the spell.
(My point about Steel Wind Strike was that you were making melee attacks while outside normal melee range, so you can make melee attacks from farther away when the rules tell you to do so. Yes, I agree, you're the one who teleports if you use Gaze to cast Steel Wind Strike, but you measure the 30' range from the Gaze target, so you could potentially hit targets 90' away from you (assuming you were 60' behind the gaze target relative to them), and teleport up to 95' afterwards (if you struck someone 30' from the Gaze target, who was 60' from you, and then teleported behind them. Possibly farther than 95' if they're bigger than medium size. You could even cast Steel Wind Strike from the other side of a wall with Gaze, and somehow hit someone 90' away from you while still behind the wall, with a melee attack - you only teleport after you hit).
------------------------------
Thought experiment: You have a gaze target 10' from you. An enemy adjacent to him is also 10' from you. You cast booming blade and use a reach weapon as the material component. Are you allowed to hit that enemy? Why or why not? What if they're 15' from you? Why or why not?
(Follow-up: Doesn't the 5' range of the spell replace the reach of the weapon? ie, if not for Gaze, can we all agree I can't attack an enemy 10' from me with Booming Blade, even if I'm using a weapon with reach?)
1) No. Because the weapon is used to strike instead of just the spell, and the weapon doesn't move through the space between you, you can't do this. You're limited by the weapon's location.
2) Reminder that D&D isn't a reality simulator, but hiding often requires holding still and somatic casting still cause rustling/rattling of your gear. That said, yes you lose the invisible condition, but you might still be fully obscured if you have a physical obstruction between yourself and all others.
3) Not at all. If you have the Invisible condition to indicate you've hidden successfully, your first attack will be at advantage. Otherwise, there's no reason that a spell coming from another spot when they're aware of casting happening should be that big of a deal.
4) No and no. No matter what, you are still the origin of the spell. However, while they don't lose their invisibility, it's possible that this could reveal their general presence depending on the spell. (This would depend on how the spell manifests. Scorching Ray should show their general area because it visibly flies from that space. Hold Person likely wouldn't, as an example, because it isn't a glaringly obvious series of fire shots.)
5) They cannot. Not only that, but Counterspell is one of the biggest advantages you have, as you can treat yourself as being in the other space and counter them even while you're out of range.
This is not RAW nor likely even RAI. Hiding's invisibility specifically and only says a spell with verbal components breaks your invisibility, so only verbal component spells break it. You can cast S and M spells while hiding without breaking invisibility just fine.
(Contrast with spell invisibility, where casting any spell causes you to break it).
Rustling clothing or gear would be the result of a bad stealth roll (and if that was going to cause your hide to fail, it would have failed the moment they got to test your stealth with perception, passive or otherwise, not when you went to cast a spell. Once hiding, you keep that stealth result until you stop hiding).
You asked. You know the RAW of the spells in question (those which require an attack roll) reveals you even without verbal components. Will creatures necessarily know where you are? That depends on the situation and the ruling made by the DM at the time. But I was just giving an example of how it could be justified. Don't ask for what logic could justify the rule if you're just going to argue over a person's thoughts on the matter.
Also remember: D&D isn't, nor should it ever be, a real-world simulator. It's a game with rules that exist to keep things flowing. Any deviation from the rules should be an agreement you and your DM (and table) make, not you just pushing for a result.
No, Range and Reach are separate concepts. Usually Reach is the only one that is relevant for melee weapon attacks but due to the text of the spell the "within 5 feet" is also relevant for this attack, so you need to abide by both.
Yes, normally you can't use Booming Blade (or similar spells) with a reach weapon.
No the fact that it is a melee weapon attack is very relevant. So you can cast the spell and the target then has to be within 5 feet (measured from Ally X) but for you to be able to hit it it also needs to be within your reach with the weapon (measured from you).
You really shouldn't misrepresent the rules like that. When you cast Booming Blade you are making a weapon attack with the weapon in addition to using it as the material component but when you cast Steel Wind Strike you are making a spell attack while only using the weapon as the material component. Weapon attacks and spell attacks are not the same and that does make for a material difference here.