It uses its Lightning Breath 'in a 90-foot line that is 5 feet wide' along the deck, hitting crew and player characters alike, forcing them to make a Dexterity saving throw.
RAW, it's tough. It's making the creatures do a saving through because they can jump out of the way. The ship can't, so does that mean it doesn't take any damage because it's not included in the wording, or because... I don't know... it's made of wood? (Although it's going to have metal parts, and lightning hitting trees isn't fun).
With 'creatures making saving throws' in mind, let's say the dragon has innate spellcasting and cases a level 5 fireball smack bang in the centre of the ship. Again, creatures within the radius make a saving throw, and as per the spell, the fireball 'ignites flammable objects in the area that aren't being worn or carried' - thus wooden bits of the ship.
So... apart from being on fire (but with no damage mechanic to apply other than the fiery explosion that just took place!) - what damage does the ship take? You'd think fireballing a wood vessel would be an ideal way to damage and/or destroy it!
If neither 'creature makes save' attacks hits a ship as part of the great area of effect of these attacks, then how would any huge/gargantuan creature destroy a ship? Ignoring the crew and start tearing up the hull and the components with its melee attacks?
What's interesting (to me) in the Ghosts of Saltmarsh 'Of Ships and the Sea' section, is that you can upgrade your ship's sails to be resistant to fire damage. I mean, you'd want a fire resistant set of sails if you're getting attacked by fire! But apart from TARGETTING the sails with a spell that doesn't say 'creature makes save', how will you ever hit it?
I'm hoping this will trigger some interesting discussion (please don't just say 'RAW it's this stop asking questions'!), as I think that at higher levels when characters start travelling on the sea, through the air, etc., a lot of mechanics haven't been ironed out, and so although it's up to DM's discretion, I always like to work through the ideas and make sure I'm running a balanced game. Previously, I've ruled that when my players fireball'd a ship, the hull and all components in the range of the spell were damaged - so I'm likely going to rule the same way for monsters. However, that's easy with fireball... but what about lightning breath?
Well this is Simple, it takes the damage it doesn't really say it takes the save unless there's a Captain Helming the wheel I guess (DMS Discretion) you can as a reaction attempt to steer the ship away though that's still -7 to dexterity if your using a sailing ship. If it has resistance to fire damage. It takes the damage but only half. If it doesn't say it isn't resistant then it isn't. I believe any ship would take the normal damage roll. Also this may be the reason why object stat block monsters have a threshold.
2. What should happen based on the campaign's narrative?
Under the rules, yes, the boat should take damage and could be potentially destroyed. That, however, could cause narrative problems--if their boat is destroyed, the party is going to have to figure out some way to get to shore. This could be a fun part of the overall quest, or it could be something that slows and interrupts the narrative, so there are reasons why or why not you should have the ship destroyed.
You can also reflect the damage of the ship as various things breaking. Perhaps the mast breaks, so now the party has to go under oar power to reach shore. Perhaps there are holes in the hull, and the party has to patch it--this could be something that occurs during combat, so the party is going to have to scramble around using their actions to patch a hole (drastically slowing the rate of sinking) or using a bonus action to bail some water (slightly slowing the rate of sinking). Could add a fun layer of additional stress to the combat encounter, then give you some things the party has to do after the encounter to stay afloat.
When a character is caught in a FireBall spell, do you have all his equipment save or take damage?
With Lightning Breath as written, creatures make saves and take damage, not object. A DM of course has final say if building and vehicule are damaged by effects as well.
There are other spells or game elements that can target objects as well. Such distinction is intentional as per this official ruling in Sage Advice;
Some spells (like eldritch blast) target a creature. Some others (like fire bolt) target objects too. Does this mean that I can’t attack the door with eldritch blast? The target specifications (creature, object, or something else) in spells are intentional.
To piggyback on what plaguescarred is saying, the ship takes no damage. The breath weapon power says each creature. A boat is not a creature, so it takes no damage.
If you want to house rule it to take damage, you certainly can, and it could make some sense to do so. It would still get a save. Saves don’t necessarily represent jumping out of the way, they can also mean a targeting error, a glancing hit, or just plain luck. Either way, you’d use the object’s stats; boats have a dex modifier, they have damage immunities (psychic and poison are common) and a damage threshold to factor in.
I'd go for plot damage - the deck is scored and blackened, possibly even on fire. It has no actual efect on the ship, unless it's on fire and they leave it.
Biggest thing is whether you want it to. RAW are there to make the game fun and balanced. As a DM, you decide which rules to use and which to bend or break to keep things fun and balanced. If you think that the ship starting to take damage and making things difficult would be fun and balanced, then do it. If you think that it would be unfun or unbalanced, then don't.
Long and short is - if you ant the boat to have a chance of sinking, go for it If not, then don't!
The rules for object damage, if actually applied, will result in most area effects completely obliterating every non-living object in their path, as the most durable objects have all of 27 hit points. In practice I'm pretty sure most games only pay attention to object damage when someone is specifically trying to destroy an object, unless fighting in a particularly vulnerable environment.
The rules for object damage, if actually applied, will result in most area effects completely obliterating every non-living object in their path, as the most durable objects have all of 27 hit points. In practice I'm pretty sure most games only pay attention to object damage when someone is specifically trying to destroy an object, unless fighting in a particularly vulnerable environment.
Got to admit I've only ever done object damage on request or as flavour - I've kept it binary, so when someone dropped to the lower floor of a rotting ship, I rolled to see if the floor broke or not (it did). I've never bothered tracking HP for objects, though I have started writing a book about doors, which gives them HP.
The rules for object damage, if actually applied, will result in most area effects completely obliterating every non-living object in their path, as the most durable objects have all of 27 hit points. In practice I'm pretty sure most games only pay attention to object damage when someone is specifically trying to destroy an object, unless fighting in a particularly vulnerable environment.
Agree with you Pantgruel, and from the previous post on this subject, destryoing the airship is the intent and being a few hundred feet obove the ground is a vulnerable environment.
I might add the the 27 HP you are pointing out is (a) for a Large (10' x 10') area and (b) the suggested listing for an optional rule. In this case, that Large area could represent a portion of the ship or, if small enough, the entire thing. Also, for an object like a ship, I might consider raising the HP (to account for the additional resilience required to keep it together) and adding a damage threshold to prevent the slings and arrows from doing too much damage. I might consider giving the ship resistance, or immunity to lightning damage as it was designed to be airborne, in and around the storms. That might suggest that the designer of said ship would have put into it the ability to be able to withstand it's environment.
As for the OPs suggestion about lighting the thing on fire, if it were a waterlogged sea-going vessel, it might have resistance, or not ignite at all. A bone-dry airborne wooden object reads vulnerable to fire damage all day to me. Especially made of wood.
Now, OP, how do all of these mechanics make for a better game, in your estimation?
All of these granular details tend to slow down combat and make your ability to track what parts of kit and vehicle are damaged, unusable, on fire. It can quickly become a bit much for the singular human computer to work out.
Also, the last time you asked a question in this line it was because of a power gamer with the tendency to rules lawyer a touch. Now, I don't intend to read too far into this, but I might be sensing some back-and-forth between you and your optimizer. One post is how to keep them from forcecaging my dragon, the next is how does my dragon destroy their ship.
Rollback Post to RevisionRollBack
“Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts. Broad, wholesome, charitable views of men and things cannot be acquired by vegetating in one little corner of the earth all one's lifetime.” - Mark Twain - Innocents Abroad
The generic object rules for hp don’t quite apply to a boat. Boats have their own entries. For example, a keelboat has 100 hp, with a damage threshold of 10.
Much like with characters, the damage is abstracted. So if your boat has been hit and only has 1 hp left, it functions just as well as when it had full hp. But the next hit it takes (for at least 11 damage) it sinks. Much like you can’t call a shot when you attack a monster, you can’t attack, say, just the rudder of the boat. So the boat is either fine, or on the bottom of the ocean. Though if you really wanted to, the exhaustion rules could be pretty well applied to a boat, to represent it heavily damaged and limping into port.
Funnily enough, the whole concept of “Hit Points” was originally from an older game about “Ironsides” in a US Civil War naval battle reenactment game and then got appropriated by Gygax for D&D.
You posted in the DM’s forum so the answer is “whatever will make the best story.” If the story is best served by the heroes being able to commandeer the vessel and use it to sail off for adventure on the high seas, then the damage is minimal, mostly cosmetic, “battle scars to match its crew’s!” 🤗🏴☠️ If the story is best served by the ship needing some repairs and the party having to find a friendly port of call where they can meet an intriguing NPC… then the ship takes just enough damage for that to happen. 😉 If the story is best served by the total destruction of the vessel, and the party being shipwrecked on a deserted isle, then “ALL HANDS ABANDON SHIP!!” 😱 If the story is best served leaving things in the hands of fate, then you follow the rules:👉https://www.dndbeyond.com/vehicles/sailing-ship🤯
So many great responses - thanks to everyone for chiming in :)
For some context: I'm now four years in to running adventures in a homebrew campaign world, with the current / second 'main' campaign being aboard a ship, as the party, who average (now) levels 12-14, sail from island to island.
At the level that they are at, it's difficult to impose 'risk' and genuine threat - a slog through a dungeon with an inevitable boss-fight is definitely a way to up the ante and the tension, but when you're travelling hundreds of miles a day across an ocean it's a little different! Over the course of the adventure, the characters (and players) have learnt that the true risk is to the ship and the crew - NPCs that are mostly commoners (apart from the senior officers), and so they act as defenders of their floating home/transport, and that's where the buy-in comes from.
There's a lot of responses to feedback on, so I'll do my best (I'm going to paraphrase below rather than directly quote - and no tone has been added - I'm just summarising):
+ "You said elsewhere you had a power gamer in your party. Is this to do with that?" - Oh, no, not at all! My previous query about forcecage was a genuine one based on how that specific player is quite literal, but also will remember a ruling and bring it up in the future - so I have learnt over the years to put a lot of effort into making sure I'm prepared for scenarios that may come up, so that I can rule fairly and efficiently at the table, rather than a rule challenge slow things down. This query is separate from that, entirely! It just so happened that both examples involved a dragon because in that query, a dragon fight was lined up, and in this query I personally had questions about dragon damage.
+ "Spells don't specify objects, so they don't hit them" / "Damage for flavour" / "Damage for plot"... so many mixed responses! It's empowering to know that ultimately as a DM, the final word is mine. I'm a bookish sort, though, and like to fall back on published material for my answers - but when they fall short, I turn to you friendly folk! For example:
Prior to the release of Ghosts of Saltmarsh, I would argue that vehicle mechanics were a bit vague, if not non-existent. Granted, they exist in other (earlier) campaign books, but in less thought out ways. For example, take the Dragon Cult Airship from Storm King's Thunder: It has components etc. similar to how ships operate in Saltmarsh, but its repair mechanic is completely different (I would argue, worse). I actually folded that Airship content into my first campaign (the party still have access to it), and plan to overhaul the mechanics for it to be more in-keeping with the more detailed mechanics from Saltmarsh, because I think they work better.
Saltmarsh stresses things like a) damage thresholds and b) what happens when specific components are damaged (i.e. damage to sails slows ship movement) - so damaging a vessel isn't an unthought-of of thing, nor is it meant to be avoided. If you're running a nautical campaign, the defence of the ship is vital. My group have really enjoyed upgrading their vessel to be stronger, and more durable - that's the whole point of the 'superior ship upgrades' that are part of Saltmarsh's 'Of ships and the sea' chapter. At level 12-14, players can't really craft magic items without spending months doing so, so they have to find loot or level up to get cool new powers - however, upgrading the ship gives them a cool 'moving base of operations' project to work on, too. My party have incorporated arcane force ballista (which is great with ship to ship combat, and for repelling sea monsters), they had red dragon scales woven into the sails to grant fire resistance, and they even incorporated a dragon's skull and flame gland into the figurehead to create a flamethrower (all part of the Saltmarsh upgrade content) - so they have enjoyed life aboard ship! Hence: Needing to better understand damage to objects: Because it's important in this specific style of game we're playing.
I must apologise for a fair bit of confusion caused. I probably could've kept this simpler by just asking 'Do you think lightning breath damages objects in its path?', rather than roping AoEs into it. However, both the dragon's breath and the fireball had creature-based-DEX-saves, so I thought I'd mention one with the other. In the end, I decided that yes - a dragon is devastating, and an adult dragon is going to tear a ship apart - unless it's stopped. That threat fuelled the players to leap to the ship's defence, draw its fire and try their hardest to minimise damage.
The battle that triggered the OP above was played out last night. The adult blue dragon used its breath attack on two of the flying characters, and it blasted through the sails and did huge amounts of damage, which slowed the ship (a genuine mechanic from Saltmarsh content - if a move-component is damaged, the ship's movement is affected). With the ship moving slower, the senior officers (NPCs) couldn't reposition the ship to keep the dragon in the sights of the ballista, so the party began to realise they were losing a bit of their edge. The dragon caught them off-guard on the second round with fireball centred on the main deck (it has access to the spell through innate spellcasting, a dragon variant option in the Monster Manual). Although only one of the players was hit, the fireball nearly took out two of the ship's ballista and immolated eight of the ship's crew (again, they're commoners - the number of crew hit by a spell / AoE is a mechanic found in Saltmarsh). It also totally destroyed the already damaged sails, and so the masts were obliterated and the ship lost its ability to move. The fight was wrapped up by the end of the 4th round - remember, they're 12-14 (there's four of them). The artificer cast haste on the barbarian and she tore the dragon apart. In a mad dash, three of the characters rushed to cast back to back revivify spells on the fallen crew, burning through a scroll and a truck-load of diamonds (again, at this level 'cost' and 'risk' is different to how it used to be when they were lower level and poor, lol).
And now... the ship is adrift, with no masts, and no sails. The crew are alive, but morale has dropped (another Saltmarsh mechanic for life aboard ship), even though the fallen were revived. The damaged components can be repaired, but the ship needs new masts, and they can't just magic up two huge carved trunks of wood... right? The session ended with two of the party teleporting back to land to pick up new sails from a port town, whilst two other characters stayed behind to tend to the crew, and use marvelous pigments to paint-create new masts on the deck. They've fallen behind on their journey by a day or two (which may or may not affect plot), and they've lost their red-dragon-scale sails - but they've learnt a lot, and they got a legendary-rarity magic item from the dragon (a 7th level spell gem) and the dragon left behind an egg (I followed the new suggestions in Fizban's) - so the fight wasn't in vain.
Again: I don't ask weird/complicated questions because of a table-struggle with a player - nor because I'm trying to destroy anything to make a point. I'm running a campaign where the party have high-level spells and get very creative with them, and I'm looking to rule as fairly as possible without accidentally setting a precedent that I'll later regret, or have to change at the table a few sessions later. Many of the spells, mechanics and wordings in the core books aren't really geared for high-level play (this isn't a secret to anyone, it seems), and so questions like this - the effect of an AoE that doesn't specify objects - on a vessel (for example) are things that I (personally) am more comfortable asking for other DM's insight on, rather than just hoping for the best on my interpretation alone!
Scenario:
RAW, it's tough. It's making the creatures do a saving through because they can jump out of the way. The ship can't, so does that mean it doesn't take any damage because it's not included in the wording, or because... I don't know... it's made of wood? (Although it's going to have metal parts, and lightning hitting trees isn't fun).
With 'creatures making saving throws' in mind, let's say the dragon has innate spellcasting and cases a level 5 fireball smack bang in the centre of the ship. Again, creatures within the radius make a saving throw, and as per the spell, the fireball 'ignites flammable objects in the area that aren't being worn or carried' - thus wooden bits of the ship.
So... apart from being on fire (but with no damage mechanic to apply other than the fiery explosion that just took place!) - what damage does the ship take? You'd think fireballing a wood vessel would be an ideal way to damage and/or destroy it!
If neither 'creature makes save' attacks hits a ship as part of the great area of effect of these attacks, then how would any huge/gargantuan creature destroy a ship? Ignoring the crew and start tearing up the hull and the components with its melee attacks?
What's interesting (to me) in the Ghosts of Saltmarsh 'Of Ships and the Sea' section, is that you can upgrade your ship's sails to be resistant to fire damage. I mean, you'd want a fire resistant set of sails if you're getting attacked by fire! But apart from TARGETTING the sails with a spell that doesn't say 'creature makes save', how will you ever hit it?
I'm hoping this will trigger some interesting discussion (please don't just say 'RAW it's this stop asking questions'!), as I think that at higher levels when characters start travelling on the sea, through the air, etc., a lot of mechanics haven't been ironed out, and so although it's up to DM's discretion, I always like to work through the ideas and make sure I'm running a balanced game. Previously, I've ruled that when my players fireball'd a ship, the hull and all components in the range of the spell were damaged - so I'm likely going to rule the same way for monsters. However, that's easy with fireball... but what about lightning breath?
Well this is Simple, it takes the damage it doesn't really say it takes the save unless there's a Captain Helming the wheel I guess (DMS Discretion) you can as a reaction attempt to steer the ship away though that's still -7 to dexterity if your using a sailing ship. If it has resistance to fire damage. It takes the damage but only half. If it doesn't say it isn't resistant then it isn't. I believe any ship would take the normal damage roll. Also this may be the reason why object stat block monsters have a threshold.
There are two questions you have to answer:
1. What should happen based on the rules?
2. What should happen based on the campaign's narrative?
Under the rules, yes, the boat should take damage and could be potentially destroyed. That, however, could cause narrative problems--if their boat is destroyed, the party is going to have to figure out some way to get to shore. This could be a fun part of the overall quest, or it could be something that slows and interrupts the narrative, so there are reasons why or why not you should have the ship destroyed.
You can also reflect the damage of the ship as various things breaking. Perhaps the mast breaks, so now the party has to go under oar power to reach shore. Perhaps there are holes in the hull, and the party has to patch it--this could be something that occurs during combat, so the party is going to have to scramble around using their actions to patch a hole (drastically slowing the rate of sinking) or using a bonus action to bail some water (slightly slowing the rate of sinking). Could add a fun layer of additional stress to the combat encounter, then give you some things the party has to do after the encounter to stay afloat.
When a character is caught in a FireBall spell, do you have all his equipment save or take damage?
With Lightning Breath as written, creatures make saves and take damage, not object. A DM of course has final say if building and vehicule are damaged by effects as well.
There are other spells or game elements that can target objects as well. Such distinction is intentional as per this official ruling in Sage Advice;
To piggyback on what plaguescarred is saying, the ship takes no damage. The breath weapon power says each creature. A boat is not a creature, so it takes no damage.
If you want to house rule it to take damage, you certainly can, and it could make some sense to do so. It would still get a save. Saves don’t necessarily represent jumping out of the way, they can also mean a targeting error, a glancing hit, or just plain luck. Either way, you’d use the object’s stats; boats have a dex modifier, they have damage immunities (psychic and poison are common) and a damage threshold to factor in.
I'd go for plot damage - the deck is scored and blackened, possibly even on fire. It has no actual efect on the ship, unless it's on fire and they leave it.
Biggest thing is whether you want it to. RAW are there to make the game fun and balanced. As a DM, you decide which rules to use and which to bend or break to keep things fun and balanced. If you think that the ship starting to take damage and making things difficult would be fun and balanced, then do it. If you think that it would be unfun or unbalanced, then don't.
Long and short is - if you ant the boat to have a chance of sinking, go for it If not, then don't!
Make your Artificer work with any other class with 174 Multiclassing Feats for your Artificer Multiclass Character!
DM's Guild Releases on This Thread Or check them all out on DMs Guild!
DrivethruRPG Releases on This Thread - latest release: My Character is a Werewolf: balanced rules for Lycanthropy!
I have started discussing/reviewing 3rd party D&D content on Substack - stay tuned for semi-regular posts!
The rules for object damage, if actually applied, will result in most area effects completely obliterating every non-living object in their path, as the most durable objects have all of 27 hit points. In practice I'm pretty sure most games only pay attention to object damage when someone is specifically trying to destroy an object, unless fighting in a particularly vulnerable environment.
Got to admit I've only ever done object damage on request or as flavour - I've kept it binary, so when someone dropped to the lower floor of a rotting ship, I rolled to see if the floor broke or not (it did). I've never bothered tracking HP for objects, though I have started writing a book about doors, which gives them HP.
Make your Artificer work with any other class with 174 Multiclassing Feats for your Artificer Multiclass Character!
DM's Guild Releases on This Thread Or check them all out on DMs Guild!
DrivethruRPG Releases on This Thread - latest release: My Character is a Werewolf: balanced rules for Lycanthropy!
I have started discussing/reviewing 3rd party D&D content on Substack - stay tuned for semi-regular posts!
Agree with you Pantgruel, and from the previous post on this subject, destryoing the airship is the intent and being a few hundred feet obove the ground is a vulnerable environment.
I might add the the 27 HP you are pointing out is (a) for a Large (10' x 10') area and (b) the suggested listing for an optional rule. In this case, that Large area could represent a portion of the ship or, if small enough, the entire thing. Also, for an object like a ship, I might consider raising the HP (to account for the additional resilience required to keep it together) and adding a damage threshold to prevent the slings and arrows from doing too much damage. I might consider giving the ship resistance, or immunity to lightning damage as it was designed to be airborne, in and around the storms. That might suggest that the designer of said ship would have put into it the ability to be able to withstand it's environment.
As for the OPs suggestion about lighting the thing on fire, if it were a waterlogged sea-going vessel, it might have resistance, or not ignite at all. A bone-dry airborne wooden object reads vulnerable to fire damage all day to me. Especially made of wood.
Now, OP, how do all of these mechanics make for a better game, in your estimation?
All of these granular details tend to slow down combat and make your ability to track what parts of kit and vehicle are damaged, unusable, on fire. It can quickly become a bit much for the singular human computer to work out.
Also, the last time you asked a question in this line it was because of a power gamer with the tendency to rules lawyer a touch. Now, I don't intend to read too far into this, but I might be sensing some back-and-forth between you and your optimizer. One post is how to keep them from forcecaging my dragon, the next is how does my dragon destroy their ship.
“Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts. Broad, wholesome, charitable views of men and things cannot be acquired by vegetating in one little corner of the earth all one's lifetime.” - Mark Twain - Innocents Abroad
The generic object rules for hp don’t quite apply to a boat. Boats have their own entries. For example, a keelboat has 100 hp, with a damage threshold of 10.
Much like with characters, the damage is abstracted. So if your boat has been hit and only has 1 hp left, it functions just as well as when it had full hp. But the next hit it takes (for at least 11 damage) it sinks. Much like you can’t call a shot when you attack a monster, you can’t attack, say, just the rudder of the boat. So the boat is either fine, or on the bottom of the ocean.
Though if you really wanted to, the exhaustion rules could be pretty well applied to a boat, to represent it heavily damaged and limping into port.
Funnily enough, the whole concept of “Hit Points” was originally from an older game about “Ironsides” in a US Civil War naval battle reenactment game and then got appropriated by Gygax for D&D.
You posted in the DM’s forum so the answer is “whatever will make the best story.” If the story is best served by the heroes being able to commandeer the vessel and use it to sail off for adventure on the high seas, then the damage is minimal, mostly cosmetic, “battle scars to match its crew’s!” 🤗🏴☠️ If the story is best served by the ship needing some repairs and the party having to find a friendly port of call where they can meet an intriguing NPC… then the ship takes just enough damage for that to happen. 😉 If the story is best served by the total destruction of the vessel, and the party being shipwrecked on a deserted isle, then “ALL HANDS ABANDON SHIP!!” 😱 If the story is best served leaving things in the hands of fate, then you follow the rules:👉https://www.dndbeyond.com/vehicles/sailing-ship🤯
Creating Epic Boons on DDB
DDB Buyers' Guide
Hardcovers, DDB & You
Content Troubleshooting
So many great responses - thanks to everyone for chiming in :)
For some context: I'm now four years in to running adventures in a homebrew campaign world, with the current / second 'main' campaign being aboard a ship, as the party, who average (now) levels 12-14, sail from island to island.
At the level that they are at, it's difficult to impose 'risk' and genuine threat - a slog through a dungeon with an inevitable boss-fight is definitely a way to up the ante and the tension, but when you're travelling hundreds of miles a day across an ocean it's a little different! Over the course of the adventure, the characters (and players) have learnt that the true risk is to the ship and the crew - NPCs that are mostly commoners (apart from the senior officers), and so they act as defenders of their floating home/transport, and that's where the buy-in comes from.
There's a lot of responses to feedback on, so I'll do my best (I'm going to paraphrase below rather than directly quote - and no tone has been added - I'm just summarising):
+ "You said elsewhere you had a power gamer in your party. Is this to do with that?" - Oh, no, not at all! My previous query about forcecage was a genuine one based on how that specific player is quite literal, but also will remember a ruling and bring it up in the future - so I have learnt over the years to put a lot of effort into making sure I'm prepared for scenarios that may come up, so that I can rule fairly and efficiently at the table, rather than a rule challenge slow things down. This query is separate from that, entirely! It just so happened that both examples involved a dragon because in that query, a dragon fight was lined up, and in this query I personally had questions about dragon damage.
+ "Spells don't specify objects, so they don't hit them" / "Damage for flavour" / "Damage for plot"... so many mixed responses! It's empowering to know that ultimately as a DM, the final word is mine. I'm a bookish sort, though, and like to fall back on published material for my answers - but when they fall short, I turn to you friendly folk! For example:
I must apologise for a fair bit of confusion caused. I probably could've kept this simpler by just asking 'Do you think lightning breath damages objects in its path?', rather than roping AoEs into it. However, both the dragon's breath and the fireball had creature-based-DEX-saves, so I thought I'd mention one with the other. In the end, I decided that yes - a dragon is devastating, and an adult dragon is going to tear a ship apart - unless it's stopped. That threat fuelled the players to leap to the ship's defence, draw its fire and try their hardest to minimise damage.
The battle that triggered the OP above was played out last night. The adult blue dragon used its breath attack on two of the flying characters, and it blasted through the sails and did huge amounts of damage, which slowed the ship (a genuine mechanic from Saltmarsh content - if a move-component is damaged, the ship's movement is affected). With the ship moving slower, the senior officers (NPCs) couldn't reposition the ship to keep the dragon in the sights of the ballista, so the party began to realise they were losing a bit of their edge. The dragon caught them off-guard on the second round with fireball centred on the main deck (it has access to the spell through innate spellcasting, a dragon variant option in the Monster Manual). Although only one of the players was hit, the fireball nearly took out two of the ship's ballista and immolated eight of the ship's crew (again, they're commoners - the number of crew hit by a spell / AoE is a mechanic found in Saltmarsh). It also totally destroyed the already damaged sails, and so the masts were obliterated and the ship lost its ability to move. The fight was wrapped up by the end of the 4th round - remember, they're 12-14 (there's four of them). The artificer cast haste on the barbarian and she tore the dragon apart. In a mad dash, three of the characters rushed to cast back to back revivify spells on the fallen crew, burning through a scroll and a truck-load of diamonds (again, at this level 'cost' and 'risk' is different to how it used to be when they were lower level and poor, lol).
And now... the ship is adrift, with no masts, and no sails. The crew are alive, but morale has dropped (another Saltmarsh mechanic for life aboard ship), even though the fallen were revived. The damaged components can be repaired, but the ship needs new masts, and they can't just magic up two huge carved trunks of wood... right? The session ended with two of the party teleporting back to land to pick up new sails from a port town, whilst two other characters stayed behind to tend to the crew, and use marvelous pigments to paint-create new masts on the deck. They've fallen behind on their journey by a day or two (which may or may not affect plot), and they've lost their red-dragon-scale sails - but they've learnt a lot, and they got a legendary-rarity magic item from the dragon (a 7th level spell gem) and the dragon left behind an egg (I followed the new suggestions in Fizban's) - so the fight wasn't in vain.
Again: I don't ask weird/complicated questions because of a table-struggle with a player - nor because I'm trying to destroy anything to make a point. I'm running a campaign where the party have high-level spells and get very creative with them, and I'm looking to rule as fairly as possible without accidentally setting a precedent that I'll later regret, or have to change at the table a few sessions later. Many of the spells, mechanics and wordings in the core books aren't really geared for high-level play (this isn't a secret to anyone, it seems), and so questions like this - the effect of an AoE that doesn't specify objects - on a vessel (for example) are things that I (personally) am more comfortable asking for other DM's insight on, rather than just hoping for the best on my interpretation alone!
Thank you all for your input!