D&D 5E Decanter of Endless Water facts


Rotten DM
Note: The England and earth’s surface calculations are 5,280 times too low. One square mile has 5,280 x 5,280 square feet, not 5,280.

Covering England to 100’ would take a bit more than 10 million years.

Covering the Earth to 1’ would take about 250 million years.

Math help which formula is right. Mine or TomB?

log in or register to remove this ad


A few comments/criticisms/questions about this...

1: My personal "view" of wizardry is that it's not an "innate spark" you must have to be able to do so (a lot of settings have this view). I agree with you that in theory, anyone could become a wizard. However in my settings not everyone has the aptitudes for it, and of those who are capable, not everyone gets the opportunity. It's a bit like being a quantum mechanics physicists - you don't need "special blood" to do it, but well, most of us couldn't hack it, and many more didn't get the chance.
And in much of my world, that would be an apt description. However, this place is different - everyone is forced to do something or be banished ... and after generations, the tendency for people to have aptitude has increased.
2: So let's say with enough education and effort, people do manage to cast magic. And they are going to study and work because they get exiled if they can't cast magic! But with this massive effort from the general population to master magic, doesn't it mean that several other crafts, fields of studies etc are going to get neglected? Would our society be better with a few more scientists? Probably - but not if everyone became a scientist. I feel this is a rather serious problem for your setting, but maybe I'm missing something?
Magic is versatile, and as mentioned, other spellcaster types also supplement the wizardry. In general, anything you can do without magic you can also do with magic, right? Especially if you have as much homebrew as I do - especially homebrew non-combat spells that would naturally evolve, but we don't see in the WotC books (such as food preservation, food preparation, entertainment, etc...)

And learning magic may be a 40 to 60 hour a week job - but how many of us do 40 to 60 hour a week jobs and have also mastered other things, such as RPG rules, board games, video games, 2nd jobs, school work, etc...
2.5: about that exile if you can't use magic, what is the deadline? How long do people have?
From the starting age (which is actually different for different heritages), you must be engaged in the pursuit of magic until you can prove your competence. If you quit without passing the test, you are banished.
3: You say sorcery is "tricks" - that's a rather different take on the "inborn/bloodline" aspect of it as usually presented in 5e. Can you elaborate on your visions for sorcerers?
I was speaking from the perspective of the intellectually aligned majority of wizards. The wizards look at sorcerers and diminish what they can do by calling their abilities tricks not born of intellect. In the same way an artist who paints masterpieces might laugh at someone that uses AI to create art or throw paint at a canvas, the wizarding world looks at sorcerers as failures that "cheat" their way to magic. They may get results, but the results are brutish and crude - not art.

And they have a point.

Sorcerers, in my world, are infused with magic. That infusion may be inherited from ancestors, but (as suggested by the PHB), it may also have been something infused into them during their lifespan. A Draconic Sorcerer might have a Draconic Ancestor, or they may have visited a wizard that grafted the essence of a dragon into their body and soul. Regardless of how that power ends up in you, it is not controlled by intellect, and is thus seen as wild and unpredictable by the wizarding world. This all plays into campaign specific concepts of how different types of spellcasters access magic:

Intelligence based spellcasters reach into the Magical Weave, craft the magic there to suit their needs with precision and intellectual force, and then release the magic. Artificers, Eldritch Knights, Wizards, Arcane Tricksters - they're all about control and precision. They utilize the dexterity of the mind.

Charisma based spellcaster also access the Magical Weave, but they use force of will to direct the magic. They don't build precise models from the magic - they funnel the chaos of the weave through the strength of their personality. An exception to this is warlocks - they use the strength of their personality to endure the delivery of the magic from the powers that grant it. They do not funnel the magic - they endure the delivery of it.

Wisdom based spellcasters access the weave as well, but they are not shaping the weave to cast their spells. Divine spellcasters accept the gifts from their divinity as fully formed gifts provided to further the will of the divine, or to reward the priest for their service.

Nature spellcasters, like druids and rangers, however, do not think in terms of accepting divine gifts. Instead, they receive the magic flowing through the weave and understand how to let it pour forth into the form of spells without shaping or manipulation - understanding how and when to let nature take its course and reach the right goal... like letting a glass drop because you know it will not break or spill. The weave extends from the core of the Positive Energy Plane and runs all the way to the core of the Negative Energy Plane. It is the beginning of all things, and the end of all things. Their affinity to it is a result of it being the most natural of forces. Why this works is something only those that walk the path understand ... and even then they only have a sense of it. Some believe it is because the Entities that exist at the Beginning and End of the Weave are like the Divine ... and what is happening is no different than a cleric, despite what druids and rangers claim. Others believe that the druids and rangers surrender part of themselves to the weave and become a part of everything, and they the weave subconciously follows their desires.

There are also psions, monks, and others that evoke types of magic that do not rely upon the weave, but they are shunned in this country.

Regardless, in this nation in particular, the intellectual elite come from generations of wizards (and artificers). They think that bards, clerics and warlocks are dangerous. They believe clerics and druids are tools of beings that possess real power - people that gave up their ability to control their own destiny. They deride and mock them - but as they can evidence their power over the universe, they are tolerated ... but not with real respect. At least not with the respect of the majority of those in power.

I've run this setting for 40 years. It has a cyclical nature that has allowed several 'in continuity' reboots for new groups that continue the legacy of the setting while allowing me to revise the setting and better address gaps, inconsistencies, and problems in the design. All in all, I'm pretty happy with how well the puzzle pieces fit together at this point.

greg kaye

... that kind of pressure, .
Even thoughts of speed are tricky.
If we think of a flow that could cover, say horizontally, a distance of 30 feet before crashing to the ground, we (with conceptions out of D&D physics) might think of something frighteningly fast.
If we thought of a continual flow, round to round that, over 6 seconds, only delivered 30 gallons of water in a 1 foot wide flow, we might think of something dawdlingly slow.

Whatever happens, the maths don't add up.

The text describes that:
"Geyser" produces 30 gallons of water that gushes forth in a geyser 30 feet long ...
then it couldn't produce a continual flow, round to round, that was:
... 1 foot wide.
On the 1 foot wide idea, it might come in geyser spurts 3-4 foot long and 1 foot wide and reaching a distance of 30 feet before gravity pulls it down.

A 1-foot wide, continual, round-to-round, 5 gallons per second (30 gallons per round) flow would only have moved 3-4 feet in one round at a speed, as I work it out, of: 0.3579 mph (with a US-based gallon) or 0.43 mph (with an Imperial-based gallon).

However it works, the result is of a not-too-challenging DC 13 strength check (that a commoner has a 35% chance of passing which, if passed, would result in no damage and, only if failed, would result in a d4 of bludgeoning damage, less than from falling 10 ft. This costs the user their action on each round of use.

The image we may get of speed probably relates to an idea of a 30 foot, potentially horizontal, stream of water needing to move fast so as to cover the distance before gravity took effect. In six seconds, in rw physics, an object can fall 579.133 feet and reach a velocity of 131.62 mph. Water bombs, from a high altitude, if anything, might work. =D

..., how viable is it as an energy source? Could it power a water wheel, or even sustain a large enough reservoir to be usefully dammed? ...
It could certainly be used as an energy source if placed at a height and, in this case, the water could even generate speed.

An internally consistent text might either describe a:
"Geyser" that produces 30 gallons of water in gushes 1 foot wide that reach a 30 foot distance in a round.
or to describe a:
"Geyser" that produces 30 gallons of water that gushes forth in a geyser 30 feet long and less than 1 foot wide.

1 US gallon = 0.133681 cubic foot by volume,
(30 US gallons = 4.01 cubic foot by volume) while;
1 Imperial gallons = 0.160544186995376 cubic foot by volume,
(30 Imperial gallons = 4.82 cubic foot by volume).

Here are calculations on view of continual flow:
Let's "speed" the water up and push it through a circular nozzle,
the ratio of the areas of a square and a circle is 4:3.14159265359... or 1:0.78539816339 (= side length of a square, squared to 1/2 diameter * π squared).
30 US gallons in a 1 ft wide "jet" would "stretch" all of:
= 3.1497843564 (feet per six-second round, less than a grid square),
30 Imperial gallons in a 1 ft wide "jet" would "stretch"all of: 30*0.160544186995376 *0.78539816339
= 3.78273328827 (feet per six-second round),
The speed of a US gallon "geyser" would be:
3.1497843564/6 = 0.5249640594 feet per second (6.3 inches per second)
= 0.3579 mph = 0.576 km/h
The speed of an Imperial gallon "geyser" would be:
3.78273328827/6 = 0.63045554804 feet per second (7.57 inches per second)
= 0.43 mph = 0.69 km/h.
Last edited:

Remove ads


Remove ads

Upcoming Releases