# Discussion:What is the hp of, oooh, a mountain?

## How much hp would an average mountain have?

### Eiji 11:35, 11 December 2007 (MST)

For the purpose of showing off the ridiculous power of a plot device, I was going to have it destroy a mountain, and for effect, come with dice rolls en masse. But how much hp would a mountain have anyway? What is the break DC?

### Daniel Draco 12:34, 11 December 2007 (MST)

Well that all depends on the size of the mountain, both in height and width. How big are you thinking? Smallest possible? Everest? Olympus mons?

### Sam Kay 13:09, 11 December 2007 (MST)

According to the DMG, "unworked stone" (i.e. the stuff a mountain would be made of) has a Break DC of 65, Hardness of 8, and 900 hp per 10ft by 10ft section. So, how big is your mountain?

Lets say you have one that is 1500 meters tall (from the ground, not sea level), and 1000 by 1000 metres on it's base. The profile is an isoscelese triangle. The area of a cone (which is simular to a mountain) is:

$\frac{\pi r^2 h}{3}$.

First, we need to convert meters to feet. 4921 ft tall, 3280 ft wide. R=1640.

$\frac{\pi \times 1640^2 \times 4921}{3} = \frac{4.158061742 \times 10^{10}}{3} = 1.386020581 \times 10^{10}$.

To get the number of $10 \text{ft}^3$:

$\frac{1.386020581 \times 10^{10}}{10} = 1386020581$.

To get the approximate number of Hp for the mountain, $1386020581 \times 900$ is $1.247418523 \times 10^{12}$.

Converted from standard form, that is $1000000000000 \times 1.247418523 = 1247418523000 \text{Hp}$.

1247418523000 Hp.

That means that you have to deal 1247418523000+(8xnumber of attacks used to destroy a mountain)= 1247418523008 for a single blow (which I assume is the point).

1247418523008

That is one mean creature...

Although this is all in approximations.

### Eiji 21:31, 11 December 2007 (MST)

Sweeeeeet jesus!

Sound good to me. I'll round it off to 1,200,000,000,000 and proceed from there. You guys are a great help! :D

### Sam Kay 08:26, 12 December 2007 (MST)

Although that is a mountain that is 1500 meters tallm and 1000 by 1000 meters base.

### 84.108.164.233 06:10, 21 February 2008 (MST)

actually, unworked stone has 900hp per 5x10x10 SRD:Epic Obstacles which means 1800hp per 10 feet cubed. 10 feet cubed is roughly 3.1 meters cubed or roughly 30 cubic meters. this means that one cubic meter has 1800/30=60hp. the volume of a 1000 meters high mountain with a cone shape is (height times area of base)/3. height is 1000. area of base is pi times 500 squared which is roughly 785,000 hence the volume of the mountain is 261,666,666 cubic meters. say 260,000,000 cubic meters. hence the hp of the mountain is 15,600,000,000. say for simplicity sake 15,000,000,000 hp. this result has 2 less digits then the one quoted above and is "only" 15 billion hp. now, that would take roughly 430,000,000 fireballs (more if caster is less than 10th level). more actually since i did not take into account hardness. does hardness count? anyway, at, say, 100 spells a day that will take, oh, 4,300,000 days or 11,780 years. it would take even more using magic missile! or 'mage hand' to remove the dirt by "hand". dammit! just dig! you lazy bastard!

Only in epic. In non epic it's 900 per 10 by 10 by 10. --Sam Kay 05:05, 30 March 2008 (MDT)

### Eiji 14:19, 21 February 2008 (MST)

This just keeps getting more awesome. :D And Fireball would do half damage since its rock, but no hardness. Use Sonic Fireballs instead.

Even better, let's give a Warforged (since he doesn't sleep or tire) an Adamantine Greatsword and assume Str 18 and no Enchantment bonus. On average he rolls a total of 6 damage and +4 Str, so 10 damage a round. That means for 15 billion hp it will take him 1,500,000,000 rounds. A round is six seconds so it will take him 150,000,000 minutes, or 2,500,000 hours, or 104167 days, or 14881 weeks, or 286 years to destroy the mountain. So we just need 286 very bored warforged to cleave apart a mountain in a year. And if we had 14,872 bored warforged we could wreck it in a week.

Get to work!

### Penske 18:21, 21 February 2008 (MST)

H.O.L.Y. C.R.A.P.

### Aarnott 19:39, 21 February 2008 (MST)

Never challenge D&D players to figure out something that doesn't seem to be in the rules. They will find rules for it. And math. Lots of math.

### TK-Squared 20:12, 20 March 2008 (MDT)

To interject at a rather later point, there is a flaw in Eiji's math. The flaw resides in his average damage. The average damage of a greatsword is 7 (1d6 average = 3.5, 2d6 average = 7). That means you're doing a total of 11 damage per hit. That's 1,363,636,364 rounds (rounded up) to destroy it rather than your crazed 1.5 billion (My 1.36 billion is much cooler). Obviously, now it'll take less time. HA!

(Let's not mention that he misses every 1 in 20 rounds)

### Ramses IV 06:31, 21 March 2008 (MDT)

I don'y know about that last 1/20 statement, TK. Walls, stone, doors, etc. have an AC of 0. All you have to bypass is the hardness to start doing damage, which you've done with the Adamantine sword. I know that rolling a 1 is normally an automatic miss, but I take the AC of 0 to mean automatic hit. I don't know if that's a houserule or not, but that's the way I was taught and the way I play today. Am I right, or does the "1 is a miss rule" still apply even to that?

### Sam Kay 06:55, 21 March 2008 (MDT)

Applying the "1 I miss rule" to a mountain is just silly (unless you are a long way away). It's not particulaly hard to hit a mountain, just hard to hurt it. Which is where hardness comes in.

### Kisame93 06:37, 30 March 2008

When i read this i cracked up!.... I hope i see the day when the mountian fall!......

Also this gave me an idea of a army of warforeged that destroys a mountian base! YAY! any1 wanna do the math for a Keep with mountains all around it.......??????

### Shadowfax 15:45, 3 April 2008

Seems like a stupid question.

If you could summon a Warforged you should be able or be close to being able to cast Wish or Limited Wish just wish it was gone. "I wish this mountain was immediatly removed from time and space." Ta Da wow I just broke a sweat.

### Sam Kay 09:53, 3 April 2008 (MDT)

What, and risk the DM removing it from time and space, and placing it back in again above your head? SQUISH! DMs can do that, you know, and many would. It's not sensible to just use wish like that, whenever you feel like it. You could end up dead. Destroying a mountain with wish is a poor plot device when used to emphasize the power of an NPC, which is what Eiji wanted to do.

### Aarnott 15:02, 3 April 2008 (MDT)

Another way to have some fun with math... According to some very brief research I did (so this might not be accurate), the average mass of rock has a density 2.7 times that of water. So... It weighs 168 pounds per cubic foot.

That would mean that we have: $weight (lbs) = 1386020581 ft.^{3} \times 168 lbs$

weight = 232,851,457,608 lbs

So... Now for the fun. How much strength does a colossal quadruped need to move a mountain? Well, it has a 120x multiplier to that of a human for pushing it, 24x to carry it. Every 10 strength quadruples its carrying capacity. As I write this I have no idea how large the Strength score is going to be by the way.

This table summarizes it's base lifting power:

##### Table: Carrying Capacity

20 9,600 lb. 48,000 lb.
21 11,040 lb. 55,200 lb.
22 12,480 lb. 62,400 lb.
23 14,400 lb. 72,000 lb.
24 16,800 lb. 84,000 lb.
25 19,200 lb. 96,000 lb.
26 22,080 lb. 110,400 lb.
27 24,960 lb. 124,800 lb.
28 28,800 lb. 144,000 lb.
29 33,600 lb. 168,000 lb.
10 ×4 ×4 ×4

So... Let's figure out what Strength "bracket" the mountain is in to push:

nsi: Number of 10 point Strength Increases

$\mbox {Weight of the mountain} = 168,000 \mbox {lb.} \times 4^{nsi}$
$232,851,457,608 \mbox {lb.} = 168,000 \mbox {lb.} \times 4^{nsi}$
$1,386,020.58 \mbox {lb.} = 4^{nsi}$
$\log _4(1,386,020.58) = \log _4(4^{nsi})$
$nsi = \frac{\log (1,386,020.58)}{\log (4)}$

nsi = 10.2

Rounding up: nsi = 11

So it needs approximately 139 strength to push a mountain (possibly up to 9 less, I'm not going to calculate that).

Now to carry it!

$\mbox {Weight of the mountain} = 33,600 \mbox {lb.} \times 4^{nsi}$
$232,851,457,608 \mbox {lb.} = 33,600 \mbox {lb.} \times 4^{nsi}$
$6,930,102.9 \mbox {lb.} = 4^{nsi}$
$\log _4(6,930,102.9) = \log _4(4^{nsi})$
$nsi = \frac{\log (6,930,102.9)}{\log (4)}$

nsi = 11.3

Rounding up: nsi = 12

So it needs approximately 149 strength to carry a mountain (possibly up to 9 less, I'm not going to calculate that).

Using the Transform spell seed it is a DC 50 to turn a human into a colossal sized quadruped permanently. That is without any mitigation (I would usually advise damage for a permanent spell).

Assuming a starting strength of 20 (15 +5 from wishes) before the transform, the character will have a +32 strength from growing colossal. this means we need to gain +97 strength.

Using the Fortify spell seed it will be a DC of 384 to increase the strength by +97. Now we mitigate it and we can realize why epic spells are stupid... Fortify lasts 20 hours. We don't need nearly that long to whip a mountain. Burn 20,000 XP → -200. Target: personal → -2. Increase casting time by 10 minutes → -20. Increase casting time by 56 days → -112. Final DC: 50.

There you go. You can now pick up mountains for the next 20 hours. Yes it takes 56 days to cast, but it is worth it! Get some levels of hulking hurler and up your strength by 10 more (+40 DC on the fortify spell, burn an extra 20 days to offset it). Then you can whip mountains at people. Who doesn't want to do that?

### TK-Squared 20:01, 7 April 2008 (MDT)

Of course, for even better mitigating circumstances... Just start gating in a few solars...

### Badger 03:30, 11 February 2010 (UTC)

Don't forget as the mountain breaks up it's still a bunch of big rocks. Conservation of Mass tells us that even when you pulverize a mountain you still have a mountain, just made of sand. You're going to need magic to explain away the dust and pebbles that are created.

### TK-Squared 15:23, 11 February 2010 (UTC)

Item casting Gust of Wind every round?

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Why not just get multiple people casting the spell?

## And what about a planet?????

well a planet(for example, earth) if around 10,000 miles diameter. so for the radius you need a 5,000 to work with. that comes down to V=(4/3)P x 125,000,000,000. 125,000,000,000 miles=660,000,000,000,000 feet so now you now have V=4.188 x 660,000,000,000,000. so that comes out to be.....2,764,080,000,000,000 cubic feet, devide by ten(because of the 10x10x10 thingy) and you then get...276,408,000,000,000 now you multiply by 900(non-epic) to get 248,767,200,000,000,000. and if you are in epic then it would be....497,534,400,000,000,000 so non-epic would have 248,767,200,000,000,000 HP(that is one hell of a hit) and epic is 497,534,400,000,000,000 hp(even harder =D) and if you do decide to do this, you must(if DM wants their playing feild to stay intact that is...) consider all the goodie-goodie clerics around the world(with a world of this size and stuff you would have 6,802,000,000 people, 90% of which are normal weaklings...75577777 not so normal people, devide it equaly between the classes(base only) and you have.....5,038,518 of each class so you have 5,038,518 clerics alone... minus about 25%(not all evil want the world gone...)201,540 people that would try to repair the earth. not to mention the fact that druids & rangers can heal too. so you now have clerics + druids + rangers(of which i will half, because they arnet as good at it.) or in simplerer (and not so nerdy terms :D) 705392people all casting cure serious wounds on earth, and then you have the same amount of wizards, sorcerers, and bards all casting repair object and stuff so basicly i think that earth would turn to dust, all PC's trying to destroy earth are sucks in by gravity(like quicksand :D) and the NPC magic uses repair it, killing anyone inside instantly, and technicly they could heal the earth allot faster and easyer that a person could destroy it(as each would now only have to heal 352,665,129,197.64562782969094100387 hp and such over the course it takes you to recharge this weapon and such.) and if you really want to know if chuck noris can push the world...calculate the frickin carrying capacity thing yourself....

hey if anyone knows how...to..um...make this look like it took less work...and make it look more like Sam Kay's then go ahead...im not gonna stop you...

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