Okay, but there aren't any rules for Friction, I'd agree that you would probably say that it'd difficult terrain but there are rules about moving through obstacles like walls, which prevent your suggestion of moving through walls. But no rules about friction or the weight of a creature affecting it's speed except when applying encumbaerance.
An immonile creature can't move even if it's speed is increased unless another rule trumps it. However, the specific case of the Killer Whale, and my earlier comment (very few creatures are immobile), isn't made invalid because of this.
What it says is that having a movement speed does not necessitate you being capable of using it. If you admit that then you have to admit that it needs some interpretation after that, since we're not told which creatures are immobile or (to quote the MM on the topic) "have no form of ground-based locomotion" or might have 0' speed listed for some other reason that might or might not leave them capable of using that speed.
Personally, I would say that a Shrieker is immobile but that's interpretation...
I'm not argueing whether a creature can use it's movement. That's on the DM at the table, I'm arguing that Longstrider provides a creature with +10 ro it's speed, which, RAW, means that every creature when affected by longstrider has a "walking speed" of at least 10ft per round.
The specific case of a Killer Whale, given it's range of movement in Shallow Water/Beach (not using a 'swim speed'). I am saying would be able to use the speed granted by Longstrider. Whether all the ground counts as difficult terrain or not, it is not Immobile or unable to use it's movement. Because Longstrider doesn't have any details on how it provides the movement, just that it does, the mechanics of how it works are up to personal interpretation (but should always be keeping in mind that it's magic)
I'm not argueing whether a creature can use it's movement. That's on the DM at the table, I'm arguing that Longstrider provides a creature with +10 ro it's speed, which, RAW, means that every creature when affected by longstrider has a "walking speed" of at least 10ft per round.
The specific case of a Killer Whale, given it's range of movement in Shallow Water/Beach (not using a 'swim speed'). I am saying would be able to use the speed granted by Longstrider. Whether all the ground counts as difficult terrain or not, it is not Immobile or unable to use it's movement. Because Longstrider doesn't have any details on how it provides the movement, just that it does, the mechanics of how it works are up to personal interpretation (but should always be keeping in mind that it's magic)
But I think another reasonable DM could still rule differently.
That's fine, the at the table decision is always the DM's. I'm not trying to make the point that Longstrider must be ruled this way but that it isn't wrong for it to be ruled to work this way.
Personally, I would say that a Shrieker is immobile but that's interpretation, I haven't yet seen in the rules a creature other than the Shrieker that as described is immobile. Note: I am interpreting immobile in terms of speed not in terms of any movement at all. There's a feature of the Shrieker that says when it's not moving, X effect, which I interprete to be moving in place (like the movement of an unconscious person in their breathing)
Yeah, it doesn't take any movement to sway in place.
Rollback Post to RevisionRollBack
"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?"
So longstrider gives you a flying speed and a tunneling speed?
Rollback Post to RevisionRollBack
All stars fade. Some stars forever fall. ------------------------------------------------------------------------------------------------- Homebrew:Magic Items,Monsters,Spells,Subclasses ------------------------------------------------------------------------------------------------- If there was no light, people wouldn't fear the dark.
So longstrider gives you a flying speed and a tunneling speed?
No it doesn't, or at least no sane DM would agree that it does.
So the killer whale should not get a walking speed, only +10 ft. to their swimming speed.
Rollback Post to RevisionRollBack
All stars fade. Some stars forever fall. ------------------------------------------------------------------------------------------------- Homebrew:Magic Items,Monsters,Spells,Subclasses ------------------------------------------------------------------------------------------------- If there was no light, people wouldn't fear the dark.
No, because a Killer Whale RAW already has a walking speed, it's just a walking speed of 0
Longstrider provides an increase to speed (when used generically this normally is the term given for walking speed but could be applied to any existing speed) but does not give you any increase to a speed that you don't already have.
See the phrasing difference with Fly.
To use an alternative example: An Adult Black Dragon, it's unmodified movement is
Speed40 ft., fly 80 ft., swim 40 ft.
Note only the non-walking speeds are explicitly identified. I would rule that Longstrider adds 10ft to every one of those mentioned skills, but not add new ones.
Now, looking at a Killer Whale
Speed0 ft., swim 60 ft.
The same principle applies, without adding a speed that isn't there (See there isn't Fly 0ft because the killer whale cannot fly) you can add 10ft to it's "Walking Speed"
This is a quirk of RAW and thus I wouldn't question any DM that doesn't allow a Longstrider-ed Killer Whale to travel 10ft per round on land, but likewise, it isn't disallowed in RAW.
For the sake of argument: Taking RAW to the extreme, Longstrider only provides +10ft walking speed, as walking speed is the only speed that can be referred to as "speed" without a further description of type.
Out of interest, there are only two 'monsters' in the Game Rules>Monsters that do not have a walking speed (I don't know what they are because I haven't gone through all 93 pages yet) to check, apply Movement Filter "Walk" there's only 3 results on the last page but without the filter there are 5, this may be an error but I'll update this post when I find out which they are.
But assuming this is correct, this supports the interpretation that a creature with a speed 0ft, does technically have a walk speed to be affected by Longstrider, because there's potentially two creatures that don't
Edit: I am leaving the above as is for the sake of records, but have discovered that the two creatures that don't appear when filtering for a walk speed are, these may contain spoilers for the adventures they are from:
Amble (From Locathah Rising)
Left Hand of Manshoon (From Waterdeep:DotMM)
The Left Hand can hover so maybe that's why it doesn't count for walking (Speed30 ft., can hover) but Amble doesn't appear to have anything explaining why it's not present on a walk filter (possibly a minor error, I don't believe any sane person actually uses the Walk filter, as it doesn't filter anything out (other than the above two entries))
It isn't what the spell says but what the spell doesn't say. When a feature gives access to a non-walking speed (whether increase or the presence of one) it always states the speed catagory/type.
But Monk Unarmoured movement doesn't, it just states Speed "Starting at 2nd level, your speed increases by 10 feet while you are not wearing armor or wielding a shield."
This provides the same bonus as Longstrider (with conditions) but also (at second level) doesn't provide any "special speed" like swimming or climbing. Because when an effect provides those, it always specifies the movement type.
And again regarding Friction, there isn't a Rule or Game Mechanic that features friction, that's applicable on the table of the DM when they make the decision. This would likely be on the basis of either saying it doesn't work like this or by saying it counts as Difficult terrain but it would definitely be wrong to allow Longstrider to add a movement speed that the targetted creature does not already have access to.
Edit: From the PHB Chapter 9:Combat Section "Movement and Positioning"
Using Different Speeds
If you have more than one speed, such as your walking speed and a flying speed, you can switch back and forth between your speeds during your move. Whenever you switch, subtract the distance you've already moved from the new speed. The result determines how much farther you can move. If the result is 0 or less, you can't use the new speed during the current move.
For example, if you have a speed of 30 and a flying speed of 60 because a wizard cast the fly spell on you, you could fly 20 feet, then walk 10 feet, and then leap into the air to fly 30 feet more.
See how the rules specifies which speed when referring to multiple but in the second paragraph it only says "speed of 30" and expects you to identify that it means "walking speed of 30" but doesn't have to state it every time because it's assumed that when unspecified speed means walking speed.
See earlier in the section:
"On your turn, you can move a distance up to your speed. You can use as much or as little of your speed as you like on your turn, following the rules here.
Your movement can include jumping, climbing, and swimming. These different modes of movement can be combined with walking, or they can constitute your entire move. However you're moving, you deduct the distance of each part of your move from your speed until it is used up or until you are done moving.
The “Special Types of Movement” section in chapter 8 gives the particulars for jumping, climbing, and swimming."
Note that it mentions walking seperately from Speed but is not mentioned as one of the other options for Movement (second paragraph), the speed is assumed to be Walking until otherwise specified
I would personally use a different example, as there 100% are rules for that, see Basic Rules: Chapter 12 section titled Objects
While not explicitly stating the case for every wall, it does provide a set of rules as guidance for the DM.
Most adventures when dealing with dungeons will include the AC and HP of thing like Doors (or sometimes even Walls) according to this same principle, yes, a lot is up to the DM but unlike Friction, there are rules (as guidence) for that
The in-game normal meaning of 'Speed' unqualified is walking speed.
The meaning of "speed" is usually "whichever speed if currently relevant". If you cast Slow on a creature with multiple speeds, its speed is halved no matter which one it's using, and flying or swimming creatures can take the Dash action to fly or swim further, not just walk further.
Note that the Monster Manual introduction explicitly says that a monster with a walking speed of 0 doesn't have the capacity for ground movement:
A monster's speed tells you how far it can move on its turn.
All creatures have a walking speed, simply called the monster's speed. Creatures that have no form of ground-based locomotion have a walking speed of 0 feet.
So here's two possible rulings that rule out land whales while being consistent with the rules:
Any monster that's listed as having a base walking speed of 0 lacks the capacity to move along the ground by definition. Changing its walking speed after the fact isn't going to retroactively give it some means of locomotion.
A creature without ground-based movement is never using its walking speed, therefore Longstrider's bonus never applies to that speed.
It's been stated repeatedly that because it's magic, it gives the ability to do the thing. In this case, move along the ground. Fly being the prime example of giving a mode of movement not normally allowed to a creature.
If a creature has speed 0, Longstrider give it a bonus +10. If no other mode of movement is given then it doesn't get a bonus to those types.
Rollback Post to RevisionRollBack
"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?"
I completely agree that those are legitimate rulings, but it is also not wrong within the rules to say that land whales are a possible thing. The issue derives, for me, from the fact that 'speed' is never used to decribe a non-walking speed without the type/catagory of speed also being mentioned and that, for whatever reason, it was decided that every creature would have a speed of (at least) 0ft.
Longstrider doesn't specify a speed type, restriction or mechanism, just that the target creature gains 10ft of 'speed'. This can reasonably be assumed to apply only to speeds that it already has access to (otherwise, as in all other cases, it would state what speeds it effects).
While there is the ruling:
"All creatures have a walking speed, simply called the monster’s speed. Creatures that have no form of groundbased locomotion have a walking speed of 0 feet."
It is not stated in the inverse, it does not state that:
"Creatures with that have a walking speed of 0 feet have no form of groundbased locomotion"
Using a different example: A dolphin has a walking speed of 0ft but (I am not supporting this treatment of animals) can traverse a flat dry surface without assistance (granted it required training but that indicates that, from a logical point of view, the ruling is that a creature always has 0ft of walking speed and some creatures with 0ft walking speed have no form of groundbased locomotion)
Again, this is not seeking to require a specific ruling from the DM at the table but to clarify that the DM can fairly rule in either direction (so long as the DM is fair in the rulings with regards to consistancy)
It's been stated repeatedly that because it's magic, it gives the ability to do the thing. In this case, move along the ground. Fly being the prime example of giving a mode of movement not normally allowed to a creature.
If a creature has speed 0, Longstrider give it a bonus +10. If no other mode of movement is given then it doesn't get a bonus to those types.
Longstrider doesn't specify that the speed increase is Walking/Ground Speed, it just states speed, a demi-lich hovers, is absolutely incapable of walking but would still benefit from Longstrider. The only reason Longstrider would give a walking/ground speed increase is because that is the default speed.
I have been arguing that in the cases of creatures we can see moving on land/as close to on land as humanely witnessed (killer whale in surf on a beach, inarguably not swimming but still moving (locomotively)) not in the case of creatures wothout any speed. We can establish that creatures with 0ft walking speed are not by definition 'unable to benefit from increases to this speed' as is explicitly the case with the Restrained condition.
It's been stated repeatedly that because it's magic, it gives the ability to do the thing. In this case, move along the ground. Fly being the prime example of giving a mode of movement not normally allowed to a creature.
If a creature has speed 0, Longstrider give it a bonus +10. If no other mode of movement is given then it doesn't get a bonus to those types.
If your argument is that the spell “gives the ability to do the thing” then why do you follow that with a sentence that is false? The thing the spell actually says is about your speed, not about giving the ability to move along the ground. Having a speed doesn’t necessitate that you are capable of using it.
It's been stated repeatedly that because it's magic, it gives the ability to do the thing. In this case, move along the ground. Fly being the prime example of giving a mode of movement not normally allowed to a creature.
If a creature has speed 0, Longstrider give it a bonus +10. If no other mode of movement is given then it doesn't get a bonus to those types.
Fly explicitly gives you the ability to fly. Longstrider doesn't even mention walking speed.
The issue derives, for me, from the fact that 'speed' is never used to decribe a non-walking speed without the type/catagory of speed also being mentioned...
If you look at rules and features that affect speed, you'll find that "speed" is consistently used to mean "whatever speed is currently relevant". Again, look at the Dash action or spells like Ray of Frost, Haste and Slow. None of these are specific to walking. When the rules mean walking speed, they say walking speed. See for example the wood elf's Fleet of Foot trait or the Boots of Striding and Springing.
While there is the ruling: "All creatures have a walking speed, simply called the monster’s speed. Creatures that have no form of groundbased locomotion have a walking speed of 0 feet."
It is not stated in the inverse, it does not state that: "Creatures with that have a walking speed of 0 feet have no form of groundbased locomotion"
Right. Because taking a creature that does have ground-based locomotion and reducing its speed to 0 doesn't change the fact that it does have ground-based locomotion; it just means you've stopped it from using it.
Imagine if player character sheets had boxes for flying, swimming and borrow speeds and the rules said "characters without these speeds have a 0 in their character sheet." The fact that they decided to represent your lack of flying speed with a 0 doesn't imply you get to fly as soon as you get some general bonus to your speed.
Using a different example: A dolphin has a walking speed of 0ft but (I am not supporting this treatment of animals) can traverse a flat dry surface without assistance (granted it required training but that indicates that, from a logical point of view, the ruling is that a creature always has 0ft of walking speed and some creatures with 0ft walking speed have no form of groundbased locomotion)
That's an argument for giving dolphins a walking speed greater than 0.
Rollback Post to RevisionRollBack
To post a comment, please login or register a new account.
And you're saying that the spell Longstrider is unable to provide that same support?
Longstrider says, and I quote:
"You touch a creature. The target's speed increases by 10 feet until the spell ends."
Nowhere in the description does it provide any description of how it does so.
Okay, but there aren't any rules for Friction, I'd agree that you would probably say that it'd difficult terrain but there are rules about moving through obstacles like walls, which prevent your suggestion of moving through walls. But no rules about friction or the weight of a creature affecting it's speed except when applying encumbaerance.
What it says is that having a movement speed does not necessitate you being capable of using it. If you admit that then you have to admit that it needs some interpretation after that, since we're not told which creatures are immobile or (to quote the MM on the topic) "have no form of ground-based locomotion" or might have 0' speed listed for some other reason that might or might not leave them capable of using that speed.
Exactly.
I'm not argueing whether a creature can use it's movement. That's on the DM at the table, I'm arguing that Longstrider provides a creature with +10 ro it's speed, which, RAW, means that every creature when affected by longstrider has a "walking speed" of at least 10ft per round.
The specific case of a Killer Whale, given it's range of movement in Shallow Water/Beach (not using a 'swim speed'). I am saying would be able to use the speed granted by Longstrider. Whether all the ground counts as difficult terrain or not, it is not Immobile or unable to use it's movement. Because Longstrider doesn't have any details on how it provides the movement, just that it does, the mechanics of how it works are up to personal interpretation (but should always be keeping in mind that it's magic)
But I think another reasonable DM could still rule differently.
That's fine, the at the table decision is always the DM's. I'm not trying to make the point that Longstrider must be ruled this way but that it isn't wrong for it to be ruled to work this way.
Yeah, it doesn't take any movement to sway in place.
"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
So longstrider gives you a flying speed and a tunneling speed?
All stars fade. Some stars forever fall.
-------------------------------------------------------------------------------------------------
Homebrew: Magic Items, Monsters, Spells, Subclasses
-------------------------------------------------------------------------------------------------
If there was no light, people wouldn't fear the dark.
So the killer whale should not get a walking speed, only +10 ft. to their swimming speed.
All stars fade. Some stars forever fall.
-------------------------------------------------------------------------------------------------
Homebrew: Magic Items, Monsters, Spells, Subclasses
-------------------------------------------------------------------------------------------------
If there was no light, people wouldn't fear the dark.
No, because a Killer Whale RAW already has a walking speed, it's just a walking speed of 0
Longstrider provides an increase to speed (when used generically this normally is the term given for walking speed but could be applied to any existing speed) but does not give you any increase to a speed that you don't already have.
See the phrasing difference with Fly.
To use an alternative example: An Adult Black Dragon, it's unmodified movement is
Speed 40 ft., fly 80 ft., swim 40 ft.
Note only the non-walking speeds are explicitly identified. I would rule that Longstrider adds 10ft to every one of those mentioned skills, but not add new ones.
Now, looking at a Killer Whale
Speed 0 ft., swim 60 ft.
The same principle applies, without adding a speed that isn't there (See there isn't Fly 0ft because the killer whale cannot fly) you can add 10ft to it's "Walking Speed"
This is a quirk of RAW and thus I wouldn't question any DM that doesn't allow a Longstrider-ed Killer Whale to travel 10ft per round on land, but likewise, it isn't disallowed in RAW.
For the sake of argument: Taking RAW to the extreme, Longstrider only provides +10ft walking speed, as walking speed is the only speed that can be referred to as "speed" without a further description of type.
Out of interest, there are only two 'monsters' in the Game Rules>Monsters that do not have a walking speed (I don't know what they are because I haven't gone through all 93 pages yet) to check, apply Movement Filter "Walk" there's only 3 results on the last page but without the filter there are 5, this may be an error but I'll update this post when I find out which they are.
But assuming this is correct, this supports the interpretation that a creature with a speed 0ft, does technically have a walk speed to be affected by Longstrider, because there's potentially two creatures that don't
Edit: I am leaving the above as is for the sake of records, but have discovered that the two creatures that don't appear when filtering for a walk speed are, these may contain spoilers for the adventures they are from:
Amble (From Locathah Rising)
Left Hand of Manshoon (From Waterdeep:DotMM)
The Left Hand can hover so maybe that's why it doesn't count for walking (Speed 30 ft., can hover) but Amble doesn't appear to have anything explaining why it's not present on a walk filter (possibly a minor error, I don't believe any sane person actually uses the Walk filter, as it doesn't filter anything out (other than the above two entries))
It isn't what the spell says but what the spell doesn't say. When a feature gives access to a non-walking speed (whether increase or the presence of one) it always states the speed catagory/type.
So, Fly specifies Flying speed, Tabaxi Cat's Claws specifes Climbing Speed etc
But Monk Unarmoured movement doesn't, it just states Speed "Starting at 2nd level, your speed increases by 10 feet while you are not wearing armor or wielding a shield."
This provides the same bonus as Longstrider (with conditions) but also (at second level) doesn't provide any "special speed" like swimming or climbing. Because when an effect provides those, it always specifies the movement type.
And again regarding Friction, there isn't a Rule or Game Mechanic that features friction, that's applicable on the table of the DM when they make the decision. This would likely be on the basis of either saying it doesn't work like this or by saying it counts as Difficult terrain but it would definitely be wrong to allow Longstrider to add a movement speed that the targetted creature does not already have access to.
Edit: From the PHB Chapter 9:Combat Section "Movement and Positioning"
Using Different Speeds
If you have more than one speed, such as your walking speed and a flying speed, you can switch back and forth between your speeds during your move. Whenever you switch, subtract the distance you've already moved from the new speed. The result determines how much farther you can move. If the result is 0 or less, you can't use the new speed during the current move.
For example, if you have a speed of 30 and a flying speed of 60 because a wizard cast the fly spell on you, you could fly 20 feet, then walk 10 feet, and then leap into the air to fly 30 feet more.
See how the rules specifies which speed when referring to multiple but in the second paragraph it only says "speed of 30" and expects you to identify that it means "walking speed of 30" but doesn't have to state it every time because it's assumed that when unspecified speed means walking speed.
See earlier in the section:
"On your turn, you can move a distance up to your speed. You can use as much or as little of your speed as you like on your turn, following the rules here.
Your movement can include jumping, climbing, and swimming. These different modes of movement can be combined with walking, or they can constitute your entire move. However you're moving, you deduct the distance of each part of your move from your speed until it is used up or until you are done moving.
The “Special Types of Movement” section in chapter 8 gives the particulars for jumping, climbing, and swimming."
Note that it mentions walking seperately from Speed but is not mentioned as one of the other options for Movement (second paragraph), the speed is assumed to be Walking until otherwise specified
I would personally use a different example, as there 100% are rules for that, see Basic Rules: Chapter 12 section titled Objects
While not explicitly stating the case for every wall, it does provide a set of rules as guidance for the DM.
Most adventures when dealing with dungeons will include the AC and HP of thing like Doors (or sometimes even Walls) according to this same principle, yes, a lot is up to the DM but unlike Friction, there are rules (as guidence) for that
The meaning of "speed" is usually "whichever speed if currently relevant". If you cast Slow on a creature with multiple speeds, its speed is halved no matter which one it's using, and flying or swimming creatures can take the Dash action to fly or swim further, not just walk further.
Note that the Monster Manual introduction explicitly says that a monster with a walking speed of 0 doesn't have the capacity for ground movement:
So here's two possible rulings that rule out land whales while being consistent with the rules:
It's been stated repeatedly that because it's magic, it gives the ability to do the thing. In this case, move along the ground. Fly being the prime example of giving a mode of movement not normally allowed to a creature.
If a creature has speed 0, Longstrider give it a bonus +10. If no other mode of movement is given then it doesn't get a bonus to those types.
"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
I completely agree that those are legitimate rulings, but it is also not wrong within the rules to say that land whales are a possible thing. The issue derives, for me, from the fact that 'speed' is never used to decribe a non-walking speed without the type/catagory of speed also being mentioned and that, for whatever reason, it was decided that every creature would have a speed of (at least) 0ft.
Longstrider doesn't specify a speed type, restriction or mechanism, just that the target creature gains 10ft of 'speed'. This can reasonably be assumed to apply only to speeds that it already has access to (otherwise, as in all other cases, it would state what speeds it effects).
While there is the ruling:
"All creatures have a walking speed, simply called the monster’s speed. Creatures that have no form of groundbased locomotion have a walking speed of 0 feet."
It is not stated in the inverse, it does not state that:
"Creatures with that have a walking speed of 0 feet have no form of groundbased locomotion"
Using a different example: A dolphin has a walking speed of 0ft but (I am not supporting this treatment of animals) can traverse a flat dry surface without assistance (granted it required training but that indicates that, from a logical point of view, the ruling is that a creature always has 0ft of walking speed and some creatures with 0ft walking speed have no form of groundbased locomotion)
Again, this is not seeking to require a specific ruling from the DM at the table but to clarify that the DM can fairly rule in either direction (so long as the DM is fair in the rulings with regards to consistancy)
Longstrider doesn't specify that the speed increase is Walking/Ground Speed, it just states speed, a demi-lich hovers, is absolutely incapable of walking but would still benefit from Longstrider. The only reason Longstrider would give a walking/ground speed increase is because that is the default speed.
I have been arguing that in the cases of creatures we can see moving on land/as close to on land as humanely witnessed (killer whale in surf on a beach, inarguably not swimming but still moving (locomotively)) not in the case of creatures wothout any speed. We can establish that creatures with 0ft walking speed are not by definition 'unable to benefit from increases to this speed' as is explicitly the case with the Restrained condition.
If your argument is that the spell “gives the ability to do the thing” then why do you follow that with a sentence that is false? The thing the spell actually says is about your speed, not about giving the ability to move along the ground. Having a speed doesn’t necessitate that you are capable of using it.
Fly explicitly gives you the ability to fly. Longstrider doesn't even mention walking speed.
If you look at rules and features that affect speed, you'll find that "speed" is consistently used to mean "whatever speed is currently relevant". Again, look at the Dash action or spells like Ray of Frost, Haste and Slow. None of these are specific to walking. When the rules mean walking speed, they say walking speed. See for example the wood elf's Fleet of Foot trait or the Boots of Striding and Springing.
Right. Because taking a creature that does have ground-based locomotion and reducing its speed to 0 doesn't change the fact that it does have ground-based locomotion; it just means you've stopped it from using it.
Imagine if player character sheets had boxes for flying, swimming and borrow speeds and the rules said "characters without these speeds have a 0 in their character sheet." The fact that they decided to represent your lack of flying speed with a 0 doesn't imply you get to fly as soon as you get some general bonus to your speed.
That's an argument for giving dolphins a walking speed greater than 0.