At what size do giants need the Dependency (Mana) advantage?

[Hai-Etlik]

Well, besides the mana dependency disadvantage, you might want to put the mana dependant limitation on advatages. In particular you may want to buy down stats like ST and HT, then buy them up with the limitation. That way your giant get weaker as well as taking damage.

[Fred Brackin]

Originally Posted by b-dog

I was wondering at what size making giants have the Dependency (Mana) advantage.

You need to be a little more specific.

Do you want your giants to have human-like proportions _and_ human-like athletic ability? (apparently so from later answers).

Are you excluding any Biotech-like modifications? That's a sort of slippery slope. Giraffes weren't designed with Biotech and yet they pump blood more than 7 feet straight up from their hearts to their brains. Dinosaurs did even more extreme things.

Actually trying to expand humans to larger sizes gets tricky very quickly. For example, it's often said that mass scales with the cube (volume) and strength scales with the square (cross-section).

I no longer believe this to be _quite_ true. Individual muscle fibers contact and generate force and when you're stacking them together it shouldn't matter if you stack them short and thick or long and thin.

Now bones, tendons, ligaments and other connective tissue _do_ scale by the cross-section/square and that's a definite limit on muscular strength.

So when you scale up a human to 2x size he should have 8x the muscular power but only 4x the skeletal strength and this would indeed be bad .

So you'd want to double the cross-section (and proportional weight) of his bones and general connective tissues. this would give him a lower power-to-weight ration and make him less athletic.

However, when you went 2x/4x/8x with everything some of that probably wasn't necessary.

For example, the brain is a vary large part of a human's metabolic budget. It uses up 20% of your total oxygen intake. The 2x scale man probably doesn't need 8x the brain by weight.

Only the part devoted to physical co-ordination needs to scale up. The logic thinking and verbal abilities parts don't need to increase at all.

So his brain and his whole head are probably proportionately smaller. His skull probably doesn't need to be 2x as thick either (though it might seem handy).

That means you didn't need to scale up the heart and lungs quite as much (though you did need to add some extra to the heart to pump the blood 2x as high). This in concert with needing less food to offset heat loss (a significant portion of energy intake) means you didn't have to scale up the other internal organs as much. His oversized bones aren't using up an amount of energy proportionate to their weight either.

So, muscles roughly in proportion, bones over a normally proportionate increase but brain and most internal organs in less than proportion. This means the answer is complicated and simple estimates are almost certainly wrong.

Pick an answer that fits what you want is my best advice.

[Mgellis]

Quick and dirty answer...

We may assume non-magical giants are adapted by evolution for their size. So we don't have to worry about bone density and things like that. Just look in the record of nature itself. If there have been creatures on Earth of a certain size that were bipedal, it is likely you could have giants that big without needing some magic or cosmic "support."

20-foot giants? Sure. T-Rex was that big. 200-foot giants? No. For that, you would need some kind of supernatural, cosmic, or superscience reason why they don't just collapse under their own weight. Where is the limit? I have no idea. I'd just call it 30 feet (SM +4) and go with it.

For magic-dependent giants, it should be Dependency (Mana, Very Common, Constantly) [-25]. Mana is Very Constant. Like air. It's either there or it's not. Along with taking damage, it would be a 0-point feature that the giant would be paralyzed, unable to move because of his impossibly huge weight, in the same way that a zombie stops working if you suddenly drop it into a no mana zone.

I hope this helps.

Mark

[SuedodeuS]

Originally Posted by Mgellis

We may assume non-magical giants are adapted by evolution for their size. So we don't have to worry about bone density and things like that. Just look in the record of nature itself. If there have been creatures on Earth of a certain size that were bipedal, it is likely you could have giants that big without needing some magic or cosmic "support."

20-foot giants? Sure. T-Rex was that big. 200-foot giants? No. For that, you would need some kind of supernatural, cosmic, or superscience reason why they don't just collapse under their own weight. Where is the limit? I have no idea. I'd just call it 30 feet (SM +4) and go with it.

Giants tend to have a body structure very similar to humans (or, more specifically, dwarves). A T-Rex was able to be quite large due to having a body shape that would allow it - the humanoid body type probably can't handle large sizes. I think SM +2 would probably be a better cut-off for humanoid giants. Some could be on the lower end of SM +2 without Mana Dependancy, but those would be special cases.

Originally Posted by Mgellis

For magic-dependent giants, it should be Dependency (Mana, Very Common, Constantly) [-25]. Mana is Very Constant. Like air. It's either there or it's not. Along with taking damage, it would be a 0-point feature that the giant would be paralyzed, unable to move because of his impossibly huge weight, in the same way that a zombie stops working if you suddenly drop it into a no mana zone.

Are you sure a 0-point feature is appropriate here? After all, with the dependency, you're talking about a trait that causes a character to automatically die without outside assistance if they ever get into a no mana zone. With paralysis, the giant can never escape the lethal area under his own power.

[Mailanka]

Originally Posted by SuedodeuS

Giants tend to have a body structure very similar to humans (or, more specifically, dwarves). A T-Rex was able to be quite large due to having a body shape that would allow it - the humanoid body type probably can't handle large sizes. I think SM +2 would probably be a better cut-off for humanoid giants. Some could be on the lower end of SM +2 without Mana Dependancy, but those would be special cases.

If they're just up-sized humans, yeah. But when most people talk about giants, they mean "humanoid." They often differe from humans in a few, key areas. For example, most giants tend to be stockier, with heavier-looking bones. Even you suggest giants might be built more like dwarves than delicate looking humans.

That suggests to me you could probably squeeze out a few more size modifiers before larger sizes gets unfeasible. You can make some serious modifications to the human template if you're willing to stretch your defintinion of "human" in a few areas

[Erik_Nielsen]

Originally Posted by Fred Brackin

Actually trying to expand humans to larger sizes gets tricky very quickly. For example, it's often said that mass scales with the cube (volume) and strength scales with the square (cross-section).

I no longer believe this to be _quite_ true. Individual muscle fibers contact and generate force and when you're stacking them together it shouldn't matter if you stack them short and thick or long and thin.

Now bones, tendons, ligaments and other connective tissue _do_ scale by the cross-section/square and that's a definite limit on muscular strength.

In his book The Physics of Superheroes, author James Kakalios notes that the physical limit for a human-proportioned giant is 60 feet tall. Past this, the bones cannot support the structure, regardless of how well the organs have adapted. In GURPS terms, that's SM +6.

I highly recommend this book for beginner and expert alike.

[Fred Brackin]

Originally Posted by Erik_Nielsen

In his book The Physics of Superheroes, author James Kakalios notes that the physical limit for a human-proportioned giant is 60 feet tall. Past this, the bones cannot support the structure, regardless of how well the organs have adapted. In GURPS terms, that's SM +6.

That is less clear than it might be. Does he mean that the internal organs will crush themselves under their own weight or something like that?

Very few of the internal organs are directly supported by bones. The brain might be about it.

Or maybe it's something about the compressive strength of bone but whatever his reason is it needs to be explained in the book.

[blacksmith]

Originally Posted by b-dog

But the typical 8' tall person is having a hard time getting around. He tends to have all sorts of physical problems while say hill giants are running around as though they are in fine health.

The thing is that when the hight is a function of a disease process it is not surprising that they have health problems. How tall was Gigantopithicus?

[blacksmith]

Originally Posted by Icelander

The tallest human was just under an inch short of 9'. That means that Size Modifiers +2 and over is likely a good rule of thumb (though it depends heavily on the body shape and proportions of the creature in question).

Tallest Human =/= Tallest possible human do to structural limits.

[blacksmith]

Originally Posted by Fred Brackin

I no longer believe this to be _quite_ true. Individual muscle fibers contact and generate force and when you're stacking them together it shouldn't matter if you stack them short and thick or long and thin.

Yes it does. You have to think of it as stress and strain. A muscle can generate so much strain and the like, and produces stress, but from the muscle fibers point of view it does not care what the length is, it can only take so much stress. The compensatory factor is leverage that a longer bone with a longer muscle might be stronger, but bone strength would also go as the square of size.

That is a truth of structures, be they animals or bridges.



As to giants well there were some pretty big bipeds 80 million years ago or so.