And as for strength effecting your swimming. Muscle is denser than fat so the stronger a person is the less they can swim compared to a fatter or just less muscled person.
Have you actually looked at pictures of competitive swimmers? Go do an image search for someone like Michael Phelps. A fat person can survival float better than a more muscled person, but if your goal is to move effectively in water, you absolutely want strength.
Realistic rules for underwater combat basically amount to making it something no-one will actually want to play. The only weapons in the PHB that are actually functional underwater are the dagger and the spear (and both would be used much differently than they are in surface combat). Unarmed strikes are also ineffective, as are most natural weapons (if you don't see it on an aquatic creature, it probably doesn't work). The vast majority of spells would be hazardous or completely unusable (a 5' cube of water is about 4 tons; does that even count as empty?). Metal armor is going to make your sink, which might actually be beneficial if you have water breathing, because it lets you walk on the bottom instead of needing to swim.
I am with you on that whole age thing. 'I remember when' is a common statement around our old group. And my first computer was a green screen HP terminal running Unix manual dial up. Then a TRS80 model3 with 16 colors running NEWDOS.
We should have an oath: We, the Grognards of D&D, in order for form a more perfect game ... I mean, that's more of a constitution than a mere oath, but I just like the sound of it.
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Blanket disclaimer: I only ever state opinion. But I can sound terribly dogmatic - so if you feel I'm trying to tell you what to think, I'm really not, I swear. I'm telling you what I think, that's all.
And as for strength effecting your swimming. Muscle is denser than fat so the stronger a person is the less they can swim compared to a fatter or just less muscled person.
If you want to stay a float yeah less strength, more fat better. But with underwater fighting you want to stay below the surface (most likely), and thus you want muscle; not fat.
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"grandpa" Salkur, Gnome Arti/Sorc: Forged in Chaos | Pepin, Human Arti/Cleric: Goblin horde | Mixtli, Volc Genasi Arti: Champions of the Citadel | Erix Vadalitis, Human Druid: Rising from the last war |Smithy, Human Arti: Night Ravens: Black orchids for Biscotti | Tamphalic Aliprax, Dragonborn Wizard: Chronicles of the Accursed | Doc, Dwarven Cleric (2024): Adventure at Hope's End | Abathax, Tiefling Illriger: Hunt for the Balowang | Gorin Mestel, Human Arti: Descend into Avernus
Water rules aren't included because they would complicate a complicated game. Every topic of discussion would be increased 30% because they'd have to account for how it works in water. Who wants to pay for that? Especially since it's a setting that is rarely used - when's the last time that you've seen a Triton or a sea elf in your party?
Perhaps a supplement could work...not sure if it would be profitable as anything other than a PDF on DMsGuild or whatever...or maybe if they went all out and did a Planescape job on it (almost said Spelljammer...).
People are talking RAW because that's how the game works, and house rules vary by the house, so trying to find common ground is near pointless. RAW is that the rules continue as they are until the rules say otherwise - and since there are no rules for underwater (beyond what the books already say on the matter, which is very little), then things work normally, for the most part.
That said, you could easily introduce several extra rules to increase verisimilitude. They sound great...for the DM. For the players? Well...let me out it this way. If there's a way to mitigate them (eg I'm a caster, so I can cast Water Breathing, for example), then I'd be cool with it. If I can't, then we'll have issues.
For example, let's say the premise of the campaign was that we'd be on land, so I build a tanky Fighter with heavy armour. One day we have a session and you try to start a quest that involves spending the session underwater helping Merfolk or something. You then tell me that my armour, the main aspect of my character, has to be left behind because it'll either kill me or cripple me to the point that it's pointless that I'm going? You bet that I'm noping out of that. I don't want to spend four hours inventing excuses for my character to not engage with what's happening. I'm going to vote for something else...or I'm going to find something else more worthwhile to do with my evening. I'm fine letting others be the centre of attention and stuff for sessions, but when the story neuters my character like that...I still want to be involved, fighting and whatnot, and that stops me from participating.
Perhaps now you see the problem with having those rules. To be a viable part of the game, they'd only be able to be brought into play as part of an environmental hazard - for example, as part of a boss fight, restricting movement (since your tanks wouldn't be able to cross islands), which could be a very cool scenario. However, that's a very niche purpose for something that would require a lot of extra pages to explain in the rules.
It's something best left to house rules...and ones that have to be thought through carefully to stop them from excluding players.
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If you're not willing or able to to discuss in good faith, then don't be surprised if I don't respond, there are better things in life for me to do than humour you. This signature is that response.
I'd say try swimming with a weighted vest... but I don't want to be responsible for idiots who actually try and fail.
This. A friend of mine is ... well, he's a combat diver, army underwater engineer and marine archaeologist. You don't get to be much more divey than he is. And yea, the vests they use weigh like 15 kilos, which is more than enough to sink someone, and make it hard work for even the most seasoned of swimmers/divers to get back to the surface.
Oh, he's a life guard too.
But ... I already said my piece: Of course you cannot swim in armor. I'm just weighing in on the try-it-and-see angle =D
Except, as you say, don't. When trained professionals do this, they have a click-release harness, and assistance standing by. So for god's sake don't put on your trusty chain mail and jump in the local pool.
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Blanket disclaimer: I only ever state opinion. But I can sound terribly dogmatic - so if you feel I'm trying to tell you what to think, I'm really not, I swear. I'm telling you what I think, that's all.
Not singling anyone out, but it needs to be remembered that, in character, this is a fictional heroic fantasy setting, unlike the very real world we live in out of character.
Trying to swim in armor in real life is akin to jumping off a building and trying to cast feather fall. Or even running straight at a wall from just outside of a 6 second sprint away from it, then expecting to be able to just automatically stop without hitting the wall. Or doing something similar in a car, or alternatively in a car, breaking to a stop every 6 seconds and still expecting to get anywhere (other than to court for traffic law violations).
Do not try things that work in a heroic fantasy campaign in real life, especially things that could be harmful to you when they fail.
D&D game mechanics remind me of the old roadrunner cartoons. The players, aka roadrunner, loved watching Wil E. Coyote, the DM, try crazy traps to catch or kill them for lunch.
What does this have to do with the topic, one don’t try cartoon or fantasy physics in real world, your gonna have a bad time. Two, bit of idea to bridge the gap, 1) magic spell that causes heavy armor to become lighter only in liquids where such armor would normally sink. , 2) special heavy armor made specifically to get a group though this adventure., or the ability to tap air inside the armor so as to have it act like diving gear.
D&D game mechanics remind me of the old roadrunner cartoons. The players, aka roadrunner, loved watching Wil E. Coyote, the DM, try crazy traps to catch or kill them for lunch.
What does this have to do with the topic, one don’t try cartoon or fantasy physics in real world, your gonna have a bad time. Two, bit of idea to bridge the gap, 1) magic spell that causes heavy armor to become lighter only in liquids where such armor would normally sink. , 2) special heavy armor made specifically to get a group though this adventure., or the ability to tap air inside the armor so as to have it act like diving gear.
Thankfully these items already exist.
Some of them require attunement.
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"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
Water rules aren't included because they would complicate a complicated game. Every topic of discussion would be increased 30% because they'd have to account for how it works in water. Who wants to pay for that? Especially since it's a setting that is rarely used - when's the last time that you've seen a Triton or a sea elf in your party?
Got an Aquatic Elf warlock in the party I'm DM'ing right now, actually, which drives a lot of my water-focused questions! Luckily, he doesn't wear armor heavier than leather, but the activities he gets involved in often lead to the breastplate-wearing human fighter/rogue unfortunately in the water too. (The changeling rogue doesn't much care. And when the full-plate-wearing dwarf cleric was still in the group.... well, he could cast water breathing, so no issue!)
I think this topic needs a lot of thought for a water-based campaign (whether that's an undersea adventure, or a lot of time spent on boats) - likely with house rules and such. AngryGM has an example of customizing the armor table to his Pirate Campaign needs. Otherwise, with all the arguments to either side, the DM should just make a simple ruling call - either way doesn't matter - and make it known ahead of time, and move on.
Unless, as stated above, one of your players picks a water-focused race. Then you've got to think about / try a hybrid approach!
As a very general rule I would probably say something like:
- Heavy armor + swim speed = yes you can - Heavy armor + Athletics Expertise = yes you can - Heavy armor + Athletics Proficiency = you can try (roll) - Heavy armor + no Athletics = depends on how difficult the water is. Raging rapids or a whirlpool would probably be automatic failure. Anything less, you can try.
Other factors can complicate this list further (e.g. combat, trying to tow an ally etc.)
I remember a David Eddings book from years ago. In it was a number of Church Knights who wondered why the members of one order wore chainmail instead of plate armor like the other three orders. The chainmailed knight replied that their country had a lot of rivers and streams. But they did once have a precept who ordered them to wear plate armor. They threw one of the brothers in chainmail into the river and threw the precept into the river with his plate armor. The brother shed his chainmail and swam safely to the surface. Apparently the precept is still sitting on the bottom of the river considering his options. Was either the Elenium or Tamuli series. You should also check out Joel Rosenberg's "Guardians of the Flame" series and discover how to make a "Dwarf Float".
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
Realistically, a person in a D&D world who wears armor is going to be considerably more used to moving about and performing strenuous physical activity than the average person in the modern world.
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Find your own truth, choose your enemies carefully, and never deal with a dragon.
"Canon" is what's factual to D&D lore. "Cannon" is what you're going to be shot with if you keep getting the word wrong.
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
If that's how you want to rule you have every right to do so. For me though, I've seen plenty of fantasy art of Tritons and Sea Elves and Water Genasi etc wearing chain or plate. And I don't see much point in sticking with absolute realism in this instance (or many others.)
The big question you need to ask is, will it make the game more fun if my fighter or paladin starts drowning the second he falls off the boat? I can't speak for your campaign, but for mine, letting them try some kind of roll (even at disadvantage) would feel better.
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
Realistically, a person in a D&D world who wears armor is going to be considerably more used to moving about and performing strenuous physical activity than the average person in the modern world.
For a modern comparison, I would look at military personnel. A basic "combat load" would be comparable to plate armor. Uniform, boots, basic weapons load out, helmet, body armor, and three days supplies in a pack. If you use one or two boxes of Zip-Lok bags to pack and waterproof individual items in the pack that would (maybe) give you enough buoyancy for a short swim (hundred yards?) to shore. Strength might help with how fast you swim, and Constitution might help with how long you swim but buoyancy is what allows you to swim.
It would be impossible for anyone to take into account all the variables any gaming system would encounter. Things will get missed or glossed over. But fantasy is what we make of it. I have never heard of anyone even touching on decompression times when rising from the bottom too quickly.
Realistically the problem with swimming in armor is that you have negative buoyancy, not that it otherwise interferes; body armor designed to protect divers from sharks exists. You just need some combination of not needing to be on the surface (be that scuba gear or spells of water breathing) and a source of positive buoyancy (only needed if you want to stay off the bottom).
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
If that's how you want to rule you have every right to do so. For me though, I've seen plenty of fantasy art of Tritons and Sea Elves and Water Genasi etc wearing chain or plate. And I don't see much point in sticking with absolute realism in this instance (or many others.)
The big question you need to ask is, will it make the game more fun if my fighter or paladin starts drowning the second he falls off the boat? I can't speak for your campaign, but for mine, letting them try some kind of roll (even at disadvantage) would feel better.
Thats a fair ruling, i would probably make the same ruling in a boat based game, and im only human and not adapted for swiming but most of my campagins are land based so i never realy have to think about it unless they need to cross a river
I can most certanly see your side and i must say i would never have them instanly drown, there are rules on holding breath
A creature can hold its breath for a number of minutes equal to 1 + its Constitution modifier (minimum of 30 seconds). When a creature runs out of breath or is choking, it can survive for a number of rounds equal to its Constitution modifier (minimum of 1 round).
I would give them 1 round to get back on the boat and then some drowning rounds, give the spell caster some time to teleport them back up to the boat, or mabey another player with rope could dive down and tie a rope to them
I mean realisisticly you cant swim with armor on in real life I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
Realistically, a person in a D&D world who wears armor is going to be considerably more used to moving about and performing strenuous physical activity than the average person in the modern world.
For a modern comparison, I would look at military personnel. A basic "combat load" would be comparable to plate armor. Uniform, boots, basic weapons load out, helmet, body armor, and three days supplies in a pack. If you use one or two boxes of Zip-Lok bags to pack and waterproof individual items in the pack that would (maybe) give you enough buoyancy for a short swim (hundred yards?) to shore. Strength might help with how fast you swim, and Constitution might help with how long you swim but buoyancy is what allows you to swim.
It would be impossible for anyone to take into account all the variables any gaming system would encounter. Things will get missed or glossed over. But fantasy is what we make of it. I have never heard of anyone even touching on decompression times when rising from the bottom too quickly.
Just having fun with it is enough for me.
Yes plate mail and modern military gear weigh about the same, BUT some modern military gear is made knowing that the men may have to swim or wade in rivers(Navy seals) also chain mail/plate mail sinks if you put it in water, modern military gear kinda sinks but not nearly as fast
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Have you actually looked at pictures of competitive swimmers? Go do an image search for someone like Michael Phelps. A fat person can survival float better than a more muscled person, but if your goal is to move effectively in water, you absolutely want strength.
Realistic rules for underwater combat basically amount to making it something no-one will actually want to play. The only weapons in the PHB that are actually functional underwater are the dagger and the spear (and both would be used much differently than they are in surface combat). Unarmed strikes are also ineffective, as are most natural weapons (if you don't see it on an aquatic creature, it probably doesn't work). The vast majority of spells would be hazardous or completely unusable (a 5' cube of water is about 4 tons; does that even count as empty?). Metal armor is going to make your sink, which might actually be beneficial if you have water breathing, because it lets you walk on the bottom instead of needing to swim.
We should have an oath: We, the Grognards of D&D, in order for form a more perfect game ... I mean, that's more of a constitution than a mere oath, but I just like the sound of it.
Blanket disclaimer: I only ever state opinion. But I can sound terribly dogmatic - so if you feel I'm trying to tell you what to think, I'm really not, I swear. I'm telling you what I think, that's all.
If you want to stay a float yeah less strength, more fat better. But with underwater fighting you want to stay below the surface (most likely), and thus you want muscle; not fat.
"grandpa" Salkur, Gnome Arti/Sorc: Forged in Chaos | Pepin, Human Arti/Cleric: Goblin horde | Mixtli, Volc Genasi Arti: Champions of the Citadel | Erix Vadalitis, Human Druid: Rising from the last war | Smithy, Human Arti: Night Ravens: Black orchids for Biscotti | Tamphalic Aliprax, Dragonborn Wizard: Chronicles of the Accursed | Doc, Dwarven Cleric (2024): Adventure at Hope's End | Abathax, Tiefling Illriger: Hunt for the Balowang | Gorin Mestel, Human Arti: Descend into Avernus
Water rules aren't included because they would complicate a complicated game. Every topic of discussion would be increased 30% because they'd have to account for how it works in water. Who wants to pay for that? Especially since it's a setting that is rarely used - when's the last time that you've seen a Triton or a sea elf in your party?
Perhaps a supplement could work...not sure if it would be profitable as anything other than a PDF on DMsGuild or whatever...or maybe if they went all out and did a Planescape job on it (almost said Spelljammer...).
People are talking RAW because that's how the game works, and house rules vary by the house, so trying to find common ground is near pointless. RAW is that the rules continue as they are until the rules say otherwise - and since there are no rules for underwater (beyond what the books already say on the matter, which is very little), then things work normally, for the most part.
That said, you could easily introduce several extra rules to increase verisimilitude. They sound great...for the DM. For the players? Well...let me out it this way. If there's a way to mitigate them (eg I'm a caster, so I can cast Water Breathing, for example), then I'd be cool with it. If I can't, then we'll have issues.
For example, let's say the premise of the campaign was that we'd be on land, so I build a tanky Fighter with heavy armour. One day we have a session and you try to start a quest that involves spending the session underwater helping Merfolk or something. You then tell me that my armour, the main aspect of my character, has to be left behind because it'll either kill me or cripple me to the point that it's pointless that I'm going? You bet that I'm noping out of that. I don't want to spend four hours inventing excuses for my character to not engage with what's happening. I'm going to vote for something else...or I'm going to find something else more worthwhile to do with my evening. I'm fine letting others be the centre of attention and stuff for sessions, but when the story neuters my character like that...I still want to be involved, fighting and whatnot, and that stops me from participating.
Perhaps now you see the problem with having those rules. To be a viable part of the game, they'd only be able to be brought into play as part of an environmental hazard - for example, as part of a boss fight, restricting movement (since your tanks wouldn't be able to cross islands), which could be a very cool scenario. However, that's a very niche purpose for something that would require a lot of extra pages to explain in the rules.
It's something best left to house rules...and ones that have to be thought through carefully to stop them from excluding players.
If you're not willing or able to to discuss in good faith, then don't be surprised if I don't respond, there are better things in life for me to do than humour you. This signature is that response.
I'd say try swimming with a weighted vest... but I don't want to be responsible for idiots who actually try and fail.
Currently playing 5e. I grew up playing AD&D and games from Palladium Books.
This. A friend of mine is ... well, he's a combat diver, army underwater engineer and marine archaeologist. You don't get to be much more divey than he is. And yea, the vests they use weigh like 15 kilos, which is more than enough to sink someone, and make it hard work for even the most seasoned of swimmers/divers to get back to the surface.
Oh, he's a life guard too.
But ... I already said my piece: Of course you cannot swim in armor. I'm just weighing in on the try-it-and-see angle =D
Except, as you say, don't. When trained professionals do this, they have a click-release harness, and assistance standing by. So for god's sake don't put on your trusty chain mail and jump in the local pool.
Blanket disclaimer: I only ever state opinion. But I can sound terribly dogmatic - so if you feel I'm trying to tell you what to think, I'm really not, I swear. I'm telling you what I think, that's all.
Not singling anyone out, but it needs to be remembered that, in character, this is a fictional heroic fantasy setting, unlike the very real world we live in out of character.
Trying to swim in armor in real life is akin to jumping off a building and trying to cast feather fall. Or even running straight at a wall from just outside of a 6 second sprint away from it, then expecting to be able to just automatically stop without hitting the wall. Or doing something similar in a car, or alternatively in a car, breaking to a stop every 6 seconds and still expecting to get anywhere (other than to court for traffic law violations).
Do not try things that work in a heroic fantasy campaign in real life, especially things that could be harmful to you when they fail.
D&D game mechanics remind me of the old roadrunner cartoons. The players, aka roadrunner, loved watching Wil E. Coyote, the DM, try crazy traps to catch or kill them for lunch.
What does this have to do with the topic, one don’t try cartoon or fantasy physics in real world, your gonna have a bad time. Two, bit of idea to bridge the gap, 1) magic spell that causes heavy armor to become lighter only in liquids where such armor would normally sink. , 2) special heavy armor made specifically to get a group though this adventure., or the ability to tap air inside the armor so as to have it act like diving gear.
Thankfully these items already exist.
Some of them require attunement.
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
-Ilyara Thundertale
Got an Aquatic Elf warlock in the party I'm DM'ing right now, actually, which drives a lot of my water-focused questions! Luckily, he doesn't wear armor heavier than leather, but the activities he gets involved in often lead to the breastplate-wearing human fighter/rogue unfortunately in the water too. (The changeling rogue doesn't much care. And when the full-plate-wearing dwarf cleric was still in the group.... well, he could cast water breathing, so no issue!)
I think this topic needs a lot of thought for a water-based campaign (whether that's an undersea adventure, or a lot of time spent on boats) - likely with house rules and such. AngryGM has an example of customizing the armor table to his Pirate Campaign needs. Otherwise, with all the arguments to either side, the DM should just make a simple ruling call - either way doesn't matter - and make it known ahead of time, and move on.
Unless, as stated above, one of your players picks a water-focused race. Then you've got to think about / try a hybrid approach!
As a very general rule I would probably say something like:
- Heavy armor + swim speed = yes you can
- Heavy armor + Athletics Expertise = yes you can
- Heavy armor + Athletics Proficiency = you can try (roll)
- Heavy armor + no Athletics = depends on how difficult the water is. Raging rapids or a whirlpool would probably be automatic failure. Anything less, you can try.
Other factors can complicate this list further (e.g. combat, trying to tow an ally etc.)
I remember a David Eddings book from years ago. In it was a number of Church Knights who wondered why the members of one order wore chainmail instead of plate armor like the other three orders. The chainmailed knight replied that their country had a lot of rivers and streams. But they did once have a precept who ordered them to wear plate armor. They threw one of the brothers in chainmail into the river and threw the precept into the river with his plate armor. The brother shed his chainmail and swam safely to the surface. Apparently the precept is still sitting on the bottom of the river considering his options. Was either the Elenium or Tamuli series. You should also check out Joel Rosenberg's "Guardians of the Flame" series and discover how to make a "Dwarf Float".
I mean realisisticly you cant swim with armor on in real life
I work out and own a set of full body metal chainmail, that thing makes walking strenuous and i have crossed a river in it before and just walking tru water is very hard, i thought i was going to fall over and drown(we were walking to my friend's cabin and the normal way in had collapsed over the summer), the water over the river was moving slowly and at the lowest point it was 5 feet deep(im a tad over 6ft) and i decided it would be a good idea to cross(i was 16 at the time)
but yeah, Chainmail in walkable water is hard, Plate mail is imposable, also fun fact, chain mail only cost like 400-600$ for a decent set(DnD and TTRPGs have ruined my finances)
Realistically, a person in a D&D world who wears armor is going to be considerably more used to moving about and performing strenuous physical activity than the average person in the modern world.
Find your own truth, choose your enemies carefully, and never deal with a dragon.
"Canon" is what's factual to D&D lore. "Cannon" is what you're going to be shot with if you keep getting the word wrong.
If that's how you want to rule you have every right to do so. For me though, I've seen plenty of fantasy art of Tritons and Sea Elves and Water Genasi etc wearing chain or plate. And I don't see much point in sticking with absolute realism in this instance (or many others.)
The big question you need to ask is, will it make the game more fun if my fighter or paladin starts drowning the second he falls off the boat? I can't speak for your campaign, but for mine, letting them try some kind of roll (even at disadvantage) would feel better.
For a modern comparison, I would look at military personnel. A basic "combat load" would be comparable to plate armor. Uniform, boots, basic weapons load out, helmet, body armor, and three days supplies in a pack. If you use one or two boxes of Zip-Lok bags to pack and waterproof individual items in the pack that would (maybe) give you enough buoyancy for a short swim (hundred yards?) to shore. Strength might help with how fast you swim, and Constitution might help with how long you swim but buoyancy is what allows you to swim.
It would be impossible for anyone to take into account all the variables any gaming system would encounter. Things will get missed or glossed over. But fantasy is what we make of it. I have never heard of anyone even touching on decompression times when rising from the bottom too quickly.
Just having fun with it is enough for me.
Realistically the problem with swimming in armor is that you have negative buoyancy, not that it otherwise interferes; body armor designed to protect divers from sharks exists. You just need some combination of not needing to be on the surface (be that scuba gear or spells of water breathing) and a source of positive buoyancy (only needed if you want to stay off the bottom).
Thats a fair ruling, i would probably make the same ruling in a boat based game, and im only human and not adapted for swiming
but most of my campagins are land based so i never realy have to think about it unless they need to cross a river
I can most certanly see your side and i must say i would never have them instanly drown, there are rules on holding breath
A creature can hold its breath for a number of minutes equal to 1 + its Constitution modifier (minimum of 30 seconds). When a creature runs out of breath or is choking, it can survive for a number of rounds equal to its Constitution modifier (minimum of 1 round).
I would give them 1 round to get back on the boat and then some drowning rounds, give the spell caster some time to teleport them back up to the boat, or mabey another player with rope could dive down and tie a rope to them
Yes plate mail and modern military gear weigh about the same, BUT some modern military gear is made knowing that the men may have to swim or wade in rivers(Navy seals) also chain mail/plate mail sinks if you put it in water, modern military gear kinda sinks but not nearly as fast