I am planning on running an encounter where the players will be swimming in water whilst fighting creatures native to this type of terrain. None of my players have a swimming speed but they have water breathing potions which will allow them to breathe normally.
Would something such as a shark have advantage on attacks against creatures that are struggling in the water? Is that a reasonable thing to do or would it make the players feel too much like they are in a foreign terrain.
Up until now my players have been kicking absolute monster butt and this encounter is kinda made to throw them off as well.
There are already rules to inconvenience the average player underwater; basically disadvantage with many weapons and most ranged attacks, movement halved, Fire spells resisted.
If you want to make things feel even harder for those unsuited to the place, consider some environmental challenges. Add darkness and muddy obscurity that a shark can see through (blindsight). Tangled kelp fields to trap the players and conceal enemies. Have the players tossed about on strong currents (STR save to resist) then their slow movement will make coordinated responses much harder and a pack of lesser fish/sharks can swarm anyone isolated. The difference between players speed 15 vs enemies speed 40 should really hurt.
Several of those effects might result in advantage/disadvantage being applied against the players, and should really drive home the feeling of not being well adapted to the environment...
There's a section in both the PHB and the DMG which have a little bit different info in each.
Surface dwellers underwater:
Have disadvantage on their melee attacks, outside a small handful of specific weapons
Have disadvantage on ranged normal attacks, and automatically miss ranged long range attacks.
Swimming without a swim speed is at half-speed, and may even require an Athletics check depending on current, depth, or how encumbered the player is?
Swimming for long periods causes creatures without swim checks to make Constitution saves vs. exhaustion
A creature that can't breathe water is essentially following Suffocating rules the entire time they're underwater
Arguable whether or not V components can be made while a creature is holding its breath, or if allowed, what effect speaking that V component has on the number of rounds they have left to hold their breath
All of that being considered, also giving aquatic creatures advantage on their attacks is probably overboard.
Also, don't forget the ability to surround a player in 3 dimensions, giving them 26 squares that they can potentially be attacked from instead of 8! Combined with a non-swimmer's poor maneuverability compared to underwater creatures, the squishy characters should find themselves far more in jeopardy of flanking than they are used to.
I am planning on running an encounter where the players will be swimming in water whilst fighting creatures native to this type of terrain. None of my players have a swimming speed but they have water breathing potions which will allow them to breathe normally.
Would something such as a shark have advantage on attacks against creatures that are struggling in the water? Is that a reasonable thing to do or would it make the players feel too much like they are in a foreign terrain.
Up until now my players have been kicking absolute monster butt and this encounter is kinda made to throw them off as well.
What do you think?
The fact that none of your players have a swim speed is what's going to make this encounter difficult for them. The advantage aquatic creatures are going to get is from the fact that they won't suffer the disadvantages that your players will. As Regent pointed out, a great way to amp up the difficulty curve is to incorporate environmental conditions that favor the aquatic creatures. Low/no light and/or murky water can make everything past 10-30 feet heavily obscured, which provides another source of disadvantage for the players, and a potential source of advantage for the attackers.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I am planning on running an encounter where the players will be swimming in water whilst fighting creatures native to this type of terrain. None of my players have a swimming speed but they have water breathing potions which will allow them to breathe normally.
Would something such as a shark have advantage on attacks against creatures that are struggling in the water? Is that a reasonable thing to do or would it make the players feel too much like they are in a foreign terrain.
Up until now my players have been kicking absolute monster butt and this encounter is kinda made to throw them off as well.
What do you think?
Sharks typically have the "Blood Frenzy" feature on their stat block they'll have advantage on attacks pretty quickly I'd assume anyway.
Had to fight in an underwater canyon with a current once. The crab things kept solid purchase automatically but the party kept moving 5 feet closer to the foes every turn ... made a retreat almost impossible. Also pressed us into melee where the disadvantage with our weapons was really felt.
Seems like you could get creative with homebrew rules, for instance: continuous streams of bubbles from the silt could make swimming upwards almost impossible (reduced bouyancy) or perhaps murky water makes all ranged attacks over 10 feet heavily obscured. This last example is where a blind sighted creature becomes a much heavier hitter than its CR would suggest.
You should consider giving them some advantages if they take the environment into consideration, too. Grabbing strands of kelp like a ginnysack (sp?) might make them effectively invisible to blindsight (sonar camouflage) or some such. Reward thought, punish assumptions and keep it interesting !!
I would not do more than the PHB+DMG rules for underwater combat. We are , in reality, a “fish out of water” when we are in the water. The game mechanic walking speeds for medium sized creatures (30’/rd). Roughly represent a ground speed of @ 3-4 MPH, the half speed given is then about 1-2 MPH. For comparison the fastest modern swimmers (Michael Phelps, etc) can reach a whopping 6MPH for upto about 100-200 meters. This about the speed sharks cruise at. Depending on species sharks can hit peak speeds of 20-60+ MPH so they outrun us easily. Fish like swordfish, sailfish and even tuna (and aquatic mammals and birds like penguins and porpoises) can also swim this fast. Further they are all considerably more nimble in the water than we are (let alone than we are when encased on armor etc.) and they have a variety of senses that allow them to “see” through the murk and congestion of the water. Thei lateral line is a pressure detector for close range ( a few feet), some have electromagnetic sensors to detect the nervous signals of prey, others have both active and passive sonar systems allowing detection and tracking for at least 10s of meters to kilometers no matter what the visual conditions are. In a real world situation we would have disadvantage on everything basically operating as deaf, blind and encumbered while they would have advantage on everything. In the real world if it’s man vs shark you lose. The underwater rules for the game at least give you a chance.
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Wisea$$ DM and Player since 1979.
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Dear dungeon masters,
I am planning on running an encounter where the players will be swimming in water whilst fighting creatures native to this type of terrain. None of my players have a swimming speed but they have water breathing potions which will allow them to breathe normally.
Would something such as a shark have advantage on attacks against creatures that are struggling in the water? Is that a reasonable thing to do or would it make the players feel too much like they are in a foreign terrain.
Up until now my players have been kicking absolute monster butt and this encounter is kinda made to throw them off as well.
What do you think?
There are already rules to inconvenience the average player underwater; basically disadvantage with many weapons and most ranged attacks, movement halved, Fire spells resisted.
If you want to make things feel even harder for those unsuited to the place, consider some environmental challenges. Add darkness and muddy obscurity that a shark can see through (blindsight). Tangled kelp fields to trap the players and conceal enemies. Have the players tossed about on strong currents (STR save to resist) then their slow movement will make coordinated responses much harder and a pack of lesser fish/sharks can swarm anyone isolated. The difference between players speed 15 vs enemies speed 40 should really hurt.
Several of those effects might result in advantage/disadvantage being applied against the players, and should really drive home the feeling of not being well adapted to the environment...
All the relevant information here for RAW: https://www.dndbeyond.com/sources/basic-rules/combat#UnderwaterCombat
Mega Yahtzee Thread:
Highest 41: brocker2001 (#11,285).
Yahtzee of 2's: Emmber (#36,161).
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There's a section in both the PHB and the DMG which have a little bit different info in each.
Surface dwellers underwater:
All of that being considered, also giving aquatic creatures advantage on their attacks is probably overboard.
dndbeyond.com forum tags
I'm going to make this way harder than it needs to be.
Just had to edit your quote to give the full rule for that one. If a character has a swim speed then they can attack normally.
Mega Yahtzee Thread:
Highest 41: brocker2001 (#11,285).
Yahtzee of 2's: Emmber (#36,161).
Lowest 9: JoeltheWalrus (#312), Emmber (#12,505) and Dertinus (#20,953).
Also, don't forget the ability to surround a player in 3 dimensions, giving them 26 squares that they can potentially be attacked from instead of 8! Combined with a non-swimmer's poor maneuverability compared to underwater creatures, the squishy characters should find themselves far more in jeopardy of flanking than they are used to.
dndbeyond.com forum tags
I'm going to make this way harder than it needs to be.
The fact that none of your players have a swim speed is what's going to make this encounter difficult for them. The advantage aquatic creatures are going to get is from the fact that they won't suffer the disadvantages that your players will. As Regent pointed out, a great way to amp up the difficulty curve is to incorporate environmental conditions that favor the aquatic creatures. Low/no light and/or murky water can make everything past 10-30 feet heavily obscured, which provides another source of disadvantage for the players, and a potential source of advantage for the attackers.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Sharks typically have the "Blood Frenzy" feature on their stat block they'll have advantage on attacks pretty quickly I'd assume anyway.
Check out my latest homebrew: Mystic Knight (Fighter) v1.31
And the smaller ones have Pack Tactics, so it's advantage most of the time for sharks...
Had to fight in an underwater canyon with a current once. The crab things kept solid purchase automatically but the party kept moving 5 feet closer to the foes every turn ... made a retreat almost impossible. Also pressed us into melee where the disadvantage with our weapons was really felt.
Seems like you could get creative with homebrew rules, for instance: continuous streams of bubbles from the silt could make swimming upwards almost impossible (reduced bouyancy) or perhaps murky water makes all ranged attacks over 10 feet heavily obscured. This last example is where a blind sighted creature becomes a much heavier hitter than its CR would suggest.
You should consider giving them some advantages if they take the environment into consideration, too. Grabbing strands of kelp like a ginnysack (sp?) might make them effectively invisible to blindsight (sonar camouflage) or some such. Reward thought, punish assumptions and keep it interesting !!
I would not do more than the PHB+DMG rules for underwater combat. We are , in reality, a “fish out of water” when we are in the water. The game mechanic walking speeds for medium sized creatures (30’/rd). Roughly represent a ground speed of @ 3-4 MPH, the half speed given is then about 1-2 MPH. For comparison the fastest modern swimmers (Michael Phelps, etc) can reach a whopping 6MPH for upto about 100-200 meters. This about the speed sharks cruise at. Depending on species sharks can hit peak speeds of 20-60+ MPH so they outrun us easily. Fish like swordfish, sailfish and even tuna (and aquatic mammals and birds like penguins and porpoises) can also swim this fast. Further they are all considerably more nimble in the water than we are (let alone than we are when encased on armor etc.) and they have a variety of senses that allow them to “see” through the murk and congestion of the water. Thei lateral line is a pressure detector for close range ( a few feet), some have electromagnetic sensors to detect the nervous signals of prey, others have both active and passive sonar systems allowing detection and tracking for at least 10s of meters to kilometers no matter what the visual conditions are. In a real world situation we would have disadvantage on everything basically operating as deaf, blind and encumbered while they would have advantage on everything. In the real world if it’s man vs shark you lose. The underwater rules for the game at least give you a chance.
Wisea$$ DM and Player since 1979.