The difference is this:
- At some tables, you can have your centaurs climb ladders. No problem. They don't care if it breaks physical laws or makes sense.
- At some tables, they want them to climb ladders, so they come up with a magical reason because they don't want them to break physical laws.
- At some tables, you can't have centaurs climb ladders because that is like doing a pullup with three hundred extra pounds strapped to your back.
Here is where it gets interesting. Most debating do not care if you say, we do "X" at our table. Great. Good for you. Many do care if you say you should do "X" at your table. Even if you only imply it by saying/arguing centaurs can climb because they are strong enough (they are not) or if you try to force logical arguments like the billygoat argument (knowing full well a castle wall is not a stepping stone of rocks). Those "insistent" reasons, when there are obvious flaws, make it seem like you are telling a DM you should do "X," not "Y." This is especially true when you never preface your argument with: Do whatever works for your table.
The problem is that the rules break these "physical laws" and in the game world "specific beats general".
People don't have the ability to send spikes of psychic energy into each other's minds. Except when utilizing the specific rules for "mind spike".
Horses can't climb walls, but Centaurs have a specific rule that allow them to do so.
You accept one set of physical laws being broken by the rules, but refuse to accept the other. And then, and this was the part that started this debate,
blame the player for wanting you to follow the rules. Or, blame them for getting upset that you are nerfing their character because you disagree with the rules.
Dragonborn aren't immune to their elemental damages. So, should the DM rule that by spitting fire or lightning, the Dragonborn takes that same damage automatically? It makes sense, if you shoot lightning from your body, the current would be running through you. But, changing the rules for Dragonborn to debuff them is likely to raise a lot of "why?"s from the players, who are seeing you change the rules for the sole purpose of weakening them explicitly.
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Snark aside, your example is actually quite apt. Saying "centaurs must be allowed to climb walls in D&D!" is rather akin to insisting "fighters must be allowed to make wuxia leaps in D&D!" Not every campaign includes every genre.
Centaur rules allow them to climb
Jumping rules allow a fighter with an 18 strength in full plate armor to leap 7 ft straight up, then use their hands to gain an extra 3 ft (approximately) meaning that they can easily leap onto the roof of a single story house. With no check.
They may be able to roll athletics to jump even higher.
Leaping from the ground to the top of a single story home seems fairly wuxia, so... actually every strength based character can make (low grade) wuxia leaps in DnD. Per the rules.
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Yeah, but those rules are dumb. Because they break suspension of disbelief. Just like the resting rules about how you can do up to an hour's worth of strenuous activity (including fighting) during a long rest but still gain the benefits. This is clearly dumb. I don't care what the book or Mearls says. I don't care what any writer of any game book tells me. If it doesn't make sense to me as the DM, I'm going to change it. Period. And, funnily enough, the books back me up on that.
Again "Those rules are stupid" does not mean "those rules don't exist"
"I as the DM am allowed to change any rule in the game" does not mean "Players have no right to protest rule changes made in the game"
As the DM you could rule that casting fireball causes the wizard to explode into frothy cola. You have the right. But I'm not going to say that the player who told you they wanted to play an evoker wizard is being a special snowflake for complaining that that rule change is unnecessary and arbitrarily affects their character unfairly.
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I'm absolutely certain, if we here at Enworld could comb over your game, we would find plenty that is ridiculous. Probably at least one or two restrictions in place to satisfy your personal sense of verisimilitude are ridiculous to someone who is more knowledgeable on a related field of study, simply because you can't be an expert on every field.
For instance, the idea that you can lift a centaur safely with a rope is just nonsense. Completely ridiculous.
Not to "well actually you" but, if could work with enough rope.
The Inca could build boats out of nothing but rope, and I am familiar with Shibari, a japanese rope-art that uses a significant amount of rope to suspend people, potentially for hours on end, with no negative health consequences.
Give a person with the skill enough rope, and they could lift a lot of different things "safely"
I guess my question for this whole thread remains the same. Why bend your will toward finding reasons to ban or otherwise restrict a thing (or in this case to say, dragons are too heavy to fly), when the same energy and imagination could be used to find ways to make those things work? What is gained?
I agree with this question. I tend to find very little gained.
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The reason they don't is because it is implied. The rules are in the PHB. The PHB, when written, had a set of races a player could play. All those races are humanoids. But you are right, they don't. They also don't explicitly state a fish cannot climb. So fish are able to scale castle walls just like everyone else.
Actually wrong. Using the Quipper statblock we see that Fish have a speed of 0. That means that they cannot climb. They only have a swim speed, so they can only swim.
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I knew it was only a matter of time before someone brought up mountain goats. Cloven hooves and a slight build allow for climbing like this. Large single toe hooves and a horse's build would not allow this sort of climbing ability.
Could you quote the section of the book that says Centaurs have large single toe hooves? I remember that the Tabaxi claws were a DM call, because the book didn't say. I don't see anything in the Ravnica book that says what type of hooves Centaurs have either.
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Are centaurs PCs in 5e fey?.
So their torsos are probably filled with hot air, gas, flowers, and friendship.
Ravnica Centaurs are called out as being fey beings.