D&D General On the physiology of Gelatinous Cubes

[jgsugden]

It has condition immunity prone, right (in 5E)?

It can climb, but has to do an athletics check to do so (again, assuming 5E). Given the very low intelligence, it has to have a reason to do so, such as starvation or something enticing it to do so.

 

[BookTenTiger]

Gelatinous Cubes are an important part of the gut biome of a healthy dungeon. They digest leftover organic materials and carry away harsh metals that could, over time, attract dangerous parasites like rust monsters.

When a Gelatinous Cube gets too full of metal objects, it goes through a transformation. The Cube burrows into the dungeon floor. Its insides rapidly rise in acidity, melting the metal into long thin spikes that settle to the Cube's bottom. This process hollows out the cube, leaving an empty shell that becomes saturated with the minerals of the dungeon stones (similar to fossilization but a lot faster). The fossilized, hollow Cube is fragile, though; too much weight can cause its top to fall inwards, revealing all that remains of the once noble beast... A spiked pit.

 

[MichaelSomething]

Size does matter. Whenever some one talks about tripping a cube, I've always imagined it about being about two square meters. If the cube is three square meters or larger, that would push me more towards being untripible.

 

[FrogReaver]

Obviously when you trip the cube it means it didn't land on it's face but on it's edge

 

[Tonguez]

It tastes like lemon lime. Or thinks we do.

Is it a giant cell? Or truly a wild accumulation of acidic slime come to life?

I’ve always taken slimes to be the plasmodian of titanic amoeboid colonies, Gelatinous Cubes just happen to have a unique stacking arrangement amongst its indivual members.

As a colonial species without distinct specialisation in its constituent cells Gel-Cubes do not have a primary facing or foot, all cells participate in motion via extending pseudopods and acid digestion. Cubes can climb and even hang from ceilings via their pesudopods though this is rarely observed as a necessary survival function.

 

[Cordwainer Fish]

Gelatinous Cubes are an important part of the gut biome of a healthy dungeon.

In that case I don't want to know what the equivalent of colonoscopy prep is.

 

[Mannahnin]

First off, the term "trip" defines a fairly narrow action-result sequence, most notably that the thing tripped almost always falls in the direction of whatever is tripping it (i.e. if tripped from behind you fall backwards, if from in front you fall forwards, etc.). Using a shield to tip something over such that it falls away from you is not tripping it.

Had the designers meant "knock over" I think they'd have used that term.

Never mind that were it me that shield would immediately have to save vs acid damage.....

Nah, "trip" as enacted in the D&D rules has never, to the best of my knowledge, included directionality. It's been used as a single word name for a maneuver to knock an enemy prone. So yes, it's "knock over" in function and intent. Just not in name.

First, I fully regret being the person that mentioned the gelatinous cube and tripping example. No good deed goes unpunished.

Second, while all of the jello and snail examples are fun, I do think people are mistaking the ease of turning over a piece of jello with a 10' cube. Not only in terms of size, but in terms of weight. If the gelatinous cube is as light as water, then it weighs over 62,000 pounds.

If it was the same as Jell-o, however, it would weigh a little over 39,000 pounds. And have a 10'x10' base. Just ... pointing that out.

This objection was already raised with regard to Str 10 5E characters being able to grapple and hold immobile a rhino with one hand. D&D abstracts size and mass differences to a LARGE degree to facilitate heroic action against large and giant enemies and always has.

Since the gelatinous cube does not exist in reality, I suggest that the game is better served by interpreting its physical characteristics in ways which are consonant with the game rules, rather than inventing characteristics (like its weight) that the game doesn't specify in ways which create a conflict within the rules and world.

Yep. The problem isn't that it's cube-shaped, or that it's flexible. The problem is it weighs almost thirty tons. You'd need heavy machinery to overturn that. Conan is pretty strong, but unless he's driving a bulldozer, that cube ain't going anywhere it doesn't already want to go.

The game doesn't say it weighs 30 tons. If a 10' ogre were real and conformed to human proportions and weight it would be around 875lbs (figures taken from How Heavy is my Giant? Dragon issue #13). If D&D used "realistic" weights any human would be killed or incapacitated by almost any solid hit from an ogre or giant (of course, most giants would need very different proportions just to stand up- square/cube law). In the D&D rules we use hit points to simulate defense PREVENTING any such solid hit, though I think a lot of players picture their heroic characters actually being hit solidly but somehow shrugging it off, because they're not thinking about the size/mass difference and the forces involved in the course of regular play.

Sure. Because when you read comics, it is in keeping with the fiction that he can rewind time; whereas it would seem weird and break the suspension of disbelief if he tried to trip an incredibly heavy object that had a completely stable base.

Just because something is "fantasyland," doesn't mean that there aren't expectations. Now, if you just want to say, "But the rule says I can do it, so I can," that's fine. But if you're going to say, "But it's fantasyland, so anything goes," then that's not going to work for a large number of people.

Absolutely. And I think probably making gelatinous cubes immune to being tripped, knocked prone, or any other form of forced movement almost certainly suits most people's imagination/ invisible rulebooks better than making them subject to such conditions or abilities.

If you're playing under a version of the rules which allows it, you've got two real options for optimizing the experience. 1) House rule it to disallow that. 2) Conceptualize the fiction in a way which supports the rule rather than the opposite.

Maybe cubes do indeed have a "foot"/membrane for locomotion and are subject to being knocked off balance and discombobulated in a way which matches "close enough" to the mechanics for being knocked prone. Maybe they are comprised of a gelatinous mass much lighter than water, which also allows the DM and players to better rationalize the existence of cubes in dungeons where the floor isn't sturdy enough to support a 30 ton monster in a 10' space.

Is that in support of or against tripping an ooze having the same effect as tripping something with legs?

That's all down to your taste for abstraction and how simple or complex you want to make the game, I think. Hit points are a bigger abstraction, IMO. We don't need to get hung up on the word "trip" unless we choose to. What's the general fictional thing happening here? The enemy is knocked off balance and "prone". What's the mechanical effect? The enemy is momentarily at disadvantage to attack and advantage to be attacked until it stands up or rights itself using part of its movement.

I can voluntarily choose to visualize an absurdity (a human person leg-sweeping a 30 ton cube of water) or something fantastic but plausible (a human person knocking a weird supernatural monster off balance and it taking a few seconds to re-establish its orientation/bearings).

 

[Snarf Zagyg]

This objection was already raised with regard to Str 10 5E characters being able to grapple and hold immobile a rhino with one hand. D&D abstracts size and mass differences to a LARGE degree to facilitate heroic action against large and giant enemies and always has.

Since the gelatinous cube does not exist in reality, I suggest that the game is better served by interpreting its physical characteristics in ways which are consonant with the game rules, rather than inventing characteristics (like its weight) that the game doesn't specify in ways which create a conflict within the rules and world.


The game doesn't say it weighs 30 tons. If a 10' ogre were real and conformed to human proportions and weight it would be around 875lbs (figures taken from How Heavy is my Giant? Dragon issue #13). If D&D used "realistic" weights any human would be killed or incapacitated by almost any solid hit from an ogre or giant (of course, most giants would need very different proportions just to stand up- square/cube law). In the D&D rules we use hit points to simulate defense PREVENTING any such solid hit, though I think a lot of players picture their heroic characters actually being hit solidly but somehow shrugging it off, because they're not thinking about the size/mass difference and the forces involved in the course of regular play.

This points to a fundamental difference in understanding. For example, there is a vast difference between an Ogre weighing 875 pounds, and a Gelatinous Cube that would weigh somewhere between 40,000 and 60,000 pounds. Moreover, there is a difference between "tripping" something which has two legs and is tall and humanoid, as opposed to "tripping" something which is completely grounded on a 10' by 10' base.

When you go to hit points, then, you understand the nature of why they were invented and what the abstraction means. This was stated by Gygax in the 1e DMG thusly:

As has been detailed, hit points are not actually a measure of physical damage, by and large, as far as characters (and some other creatures as
well) are concerned. Therefore, the location of hits and the type of aomage caused are not germane to them. While this is not true with
respect to most monsters, it is neither necessary nor particularly useful. Lest some purist immediately object, consider the many charts and tables necessary to handle this sort of detail, and then think about how area effect spells would work. In like manner, consider all of the nasty things which face adventurers as the rules stand. Are crippling disabilities and yet more ways to meet instant death desirable in an open-ended, episodic game where participants seek to identify with lovingly detailed and developed player-character personae? Not likely! Certain death is as undesirable as a give-away campaign. Combat is a common pursuit in the vast majority of adventures, and the participants in the campaign deserve a chance to exercise intelligent choice during such confrontations. As hit points dwindle they can opt to break off the encounter and attempt to flee. With complex combat systems which stress so-called realism and feature hit location, special damage, and so on, either this option is severely limited or the rules are highly slanted towards favoring the player characters at the expense of their opponents. (Such rules as double damage and critical hits must cut both ways - in which case the life expectancy of player characters will be shortened considerably - or the monsters are being grossly misrepresented and unfairly treated by the system. I am certain you can think of many other such rules.)

One-minute rounds are devised to offer the maximum of choice with a minimum of complication. This allows the DM and the players the best of both worlds. The system assumes much activity during the course of each round. Envision, if you will, a fencing, boxing, or karate match. During the course of one minute of such competition there are numerous attacks which are unsuccessful, feints, maneuvering, and so forth. During a one minute melee round many attacks are made, but some ore mere feints, while some are blocked or parried. One, or possibly several, have the chance to actually score damage. For such chances, the dice are rolled, and if the "to hit" number is equalled or exceeded, the attack was successful, but otherwise it too was avoided, blocked, parried, or whatever. Damage scored to characters or certain monsters is actually not substantially physical - a mere nick or scratch until the lost handful of hit points are considered - it is a matter of wearing away the endurance, the luck, the magical protections.
In other words, it is a mere abstraction; to the extent that a person describes every hit as doing substantial damage, that is not a problem with hit points, but a problem with the understanding of the abstraction. As character ability increases, the character is more able to turn a hit into a glancing blow.

Turning this to the instant example, however, there is no similar way to abstract away concrete abilities like "tripping" to the extent that they apply to a gelatinous cube. That's what breaks the fiction for many people. If you want to say that the rules trump the fiction, that's fine. If you want to say that the fiction must be changed to honor the rule (so that tripping isn't tripping, but any thing that allows the desired effect to take effect) that's also your prerogative. But to tell people that "Guys in my high school used to trip 50,000 pound boulders, no big deal," is not likely to be a winning argument for those who don't feel the same way.


Finally, moving to the subject of the OP-

Ed Greenwood had an excellent article on the ecology of the Gelatinous Cube (the "athcoid") in Dragon #124. While it is not canon, obviously, it is worth considering. To answer the questions:

Does anyone have any thoughts on the physiology of a gelatinous cube and whether it's immune to certain conditions, whether it has a primary foot / face, whether it can climb walls...or be tripped.

The cube is made of gelatinous material and has no thoughts, instead behaving almost automatically, They normally travel in their "cube" shape, but can "flow" through spaces as small as 1' across. They are immune to all conditions that would effect the "mind" of any creature, which would arguably include any stunning or the like. They would not have a primary "foot" (given their flowing ability) other than the side that is currently facing down due to gravity. They have no special ability to climb, other than to "probe" or "flow" subject to gravity.

And no, IMO a gelatinous cube cannot be tripped. Although I would certainly enjoy watching someone try. Repeatedly.

 

[Mannahnin]

This points to a fundamental difference in understanding. For example, there is a vast difference between an Ogre weighing 875 pounds, and a Gelatinous Cube that would weigh somewhere between 40,000 and 60,000 pounds. Moreover, there is a difference between "tripping" something which has two legs and is tall and humanoid, as opposed to "tripping" something which is completely grounded on a 10' by 10' base.

Two points:

1. Just to confirm, do we both acknowledge that the "trip" mechanic/action in the context of D&D (3rd edition and certain power names in 4E, the Battlemaster maneuver in 5E) is a pithy name for a more general action to knock prone, not limited only to stumbling and falling due to catching one's legs on an obstacle? Or no?

2. Do you actually play that gelatinous cubes weigh 40,000 to 60,000 pounds in your games, with all the environmental limitations and side effects that implies?

I politely submit that you are importing external assumptions into the game selectively, in a manner which increases your cognitive dissonance. And that this is an action which is at least to some extent under a person's volitional control. The opposite of which, willing suspension of disbelief, is a skill I've certain you've cultivated as a D&D player.

 

[Snarf Zagyg]

Two points:

1. Just to confirm, do we both acknowledge that the "trip" mechanic/action in the context of D&D (3rd edition and certain power names in 4E, the Battlemaster maneuver in 5E) is a pithy name for a more general action to knock prone, not limited only to stumbling and falling due to catching one's legs on an obstacle? Or no?

2. Do you actually play that gelatinous cubes weigh 40,000 to 60,000 pounds in your games, with all the environmental limitations and side effects that implies?

I politely submit that you are importing external assumptions into the game selectively, in a manner which increases your cognitive dissonance. And that this is an action which is at least to some extent under a person's volitional control. The opposite of which, willing suspension of disbelief, is a skill I've certain you've cultivated as a D&D player.

First, I politely submit that when the word "trip" is used (as opposed to knock prone) I read that as exactly what it says, no more, and no less.

Second, I would further politely submit that I do not think that a gelatinous cube can be knocked prone, given what I have previously stated.

Third, I treat gelatinous cubes as exactly what they are- bizarre creatures that clean the dungeons. When I have dungeons, they have stone floors that support massive weights. As recounted in the Ed Greenwood article, the athcoids sense ahead, and thus would not fall into pits or trigger pressure traps- although they would "flow" into a pit that was of a size that they could flow back out of. I have never placed a GC in an environment, such as on the second wooden floor of an inn, where it would be an issue, as I have known people with waterbeds.

The issue of weight has come up precisely once in an adventure I have run, when an enterprising bunch of PCs deliberately had a GC pursue them partly onto to a stone bridge, and before it turned back, weakened the stone beneath it, causing it to plummet to its doom.

Fourth, I am comfortable with certain levels of cognitive dissonance. I am not comfortable with other people telling me how I should feel about the fiction of the games I run- because at a certain point, they are ceasing to explain their position, and simply telling me that I'm doing it wrong.

I'm not doing it wrong.