What would the hardness and hitpoints of a 12-foot diameter spherical boulder be?

[dead]

Reverse Gravity? Let its own weight work against it.

If it had 997hp as we've worked out above, and it fell from the point of max. velocity doing 20d6 damage (the average of which would be 70hps) then the 12' diameter boulder would hit the ground, bounce comfortably off with barely a chip and continue down the hill like an unstoppable killing machine to crush the afforementioned (and most unfortunate) spectators.

 

[Patryn of Elvenshae]

Unless the rock also took damage based on weight, which is uncapped and is 1d6 per 200 pounds, I believe.

 

[Voodoo]

The volume of a sphere is (4*pi*r^3)/3

A 6 foot radius sphere hence has a volume of (4*pi*216)/3

The volume of a 2 1/2 foot radius sphere is (4*pi*15.625)/3

Therefore a 12 foot diameter sphere weighs 13.824 times as much as a 5 foot radius sphere.

Now making two (fairly huge) assumptions:

1) Volume is directly related to HP
2) The sphere summoned by the Stone Sphere spell (Underdark) is a standard lump of rock

The Stone Sphere spell sphere has 500 HP and therefore the 12 foot radius sphere has 6912 HP.

Conclusion: This is a stupid amount of HP to be a sensible challenge for anyone to try to tackle with and therefore any kind of mathematical approach should be abandoned.

Solution: Have the boulder made of a flawed piece of stone that will fracture into small enough pieces to be considered destroyed once enough damage has been done, 100 HP sounds great.

Now if only I can think of a suitable spell to be delivered as a touch attack from my familiar in the boulders path….

 

[Shadowdweller]

Reverse Gravity? Let its own weight work against it.

Wall of force to stop it and "a million billion magic missiles"*?

Uh, Transmute Rock to Mud?

Now me, I'd use Feeblemind. Or Baleful Polymorph. Or Finger of Death.

 

[Alratan]

I think the Fabricate idea has the most style

 

[Amal Shukup]

I think the Fabricate idea has the most style

Me too.

Sadly, this option would only be available to SERIOUSLY high level casters:

"If you work with a mineral, the target is reduced to 1 cubic foot per level instead of 10 cubic feet."

Which leaves a whole lot of Boulder...

Amal

 

[Amal Shukup]

I figure opening a Gate to somewhere hostile would work. Boring though. So, for style points, cover up the Gate technique with a fun illusion (giant cricket bat whacking thing over the horizon. A Bigbyish giant hand crushing it into powder. Exploding it into a cloud of butterflies).

Polymorph any Object would do it. Style points for changing it into something fun.

Telekinetic Sphere looked good, but the thing weighs (far!)more than 5000 pounds. Sigh. Likewise, Reverse Gravity suffers from annoying area limitations. Double Sigh.

Quickly Plane Shift to a Plane with a vastly different time rate (to give yourself a couple of Months) and Research a new spell - say a much higher level version of Shrink Item, or Greater Fabricate, or Transmute Rock to Gas...

Putting up a Prismatic Wall would stop it (when the object reached the Violet bit). Would look cool too. However, as it is a competition, very clever opponents could bring the wall down with a succession of spells...

Amal