Thread: Size and 7 to 20 ft tall Gaint Races?

I'm trying to make stats for gaint races but SIZ characteristic confuses me and I've looked at other forum post and I'm still lost.

I just want SIZ rolls for;
7ft to 10ft 250 to 500 pound humanoid

8ft to 11ft 500 to 800 pound humanoid

9ft to 14ft 300 to 700 pound humanoid

14ft to 18ft 600 to 1000 pounds humanoid

18 to 20ft

This might help. The main SIZ in in BRP, not the one from Stormbringer with body frames, uses a doubling progression in the SIZ 8-88 range, which should cover small giants. Now every time you double the mass you add 8 points of SIZ.

There is a real world rule of thumb called the "square-cube" law (or "cube-square" law) that states that if you double the height of a creature, and double it's width and depths in the same proportion, you cube the mass. That means that if you make a creature twice as tall, it weights 8 times as much, if you make it 3 times as tall, it is 27 times as heavy, and so on.






Going with the weights for the heights you listed:

250 pounds is about 113kg or SIZ 17. 500 pounds is twice that for +8 SIZ, or SIZ 25. So you get a SIZ range of 17-25, the best fit for that would be 1D6+1D4+15, although I'd suggest opening up the range a little to make it a 2D6+14 or so, to better match human SIZ ranges.

500-800 pounds would be about SIZ 25-31, or 2D4+23. Again, I'd suggest opening it up to a 2D6 roll.

300-700 pounds would be SIZ 19-29. THe roll would be 2D6+17.

600-1000 pounds would be SIZ 27-33. THe roll wound be 1D6+26, but I'd suggest opening up the range to a 2D6 roll.



Now, if you are open to another method of doing things, you could use the square cube law to find weights for a given height. Assume that an average man is 5' 10" tall, and weights 170 pounds (SIZ 13) and just take the ratio of the new height to the old and cube it to get the new weight.

For example, 7' tall (84") = 1.2 times as tall, so weight is times 1.728. 170 * 1.728 = 294 pounds
8' (96") is 1.37 times as tall, for a weight of 2.58 times as much, or 439 pounds.

And so on.

Generally, the rule of thumb for larger creatures is to use the giant sizes as a reference, although I like to use troll sizes as well. This is for RuneQuest, but should apply to BRP as well.

Dark trolls stand at around 6.5 feet tall and great/cave trolls around 8 feet tall. So, SIZ 3D6+8 is around 6.5 feet and 4D6+12 is around 8 feet, so 1D6+6 represents each 2 feet difference.

A species of around 8 feet average height would have SIZ 4D6+12, 10 feet around 5D6+18, 12 feet 6D6+24, 14 feet 7D6+30, 16 feet 8D6+36, 18 feet 9D6+42 and 20 feet 10D6+48.

A 6m giant is around 20 feet tall, with a SIZ of 9D6+18, substantially different from the SIZ extrapolated from trolls. That is probably because of a troll's extremely heavy physique, in that they are very bulky and fat.

Using giant sizes, we get 7 feet 3D6+6, 9 feet 4D6+8, 11 feet 5D6+10, 13 feet 6D6+12, 15 feet 7D6+14, 17 feet 8D6+16, 20 feet 9D6+18 and so on.

So, using those two scales, you should be able to get a rough idea of the SIZ of a creature with various average heights.

Hope this helps.

The reason for the discrepancy between Troll and Giant SIZes is that Trolls follow a realistic SIZ progression and Giant's don't.

Realistically, when you double the size, you cube the mass. In game terms that means that if you double the height you add 24 to SIZ.

Trolls basically follow that progression. Increasing from 6' 6"' to 8' is approximately a 25% increase in height and cubed that works out to about double the weight, or 8 points more of SIZ.

But the old Giant stats simply give 3D6+6 SIZ per 2m, so old style giants actually get less dense as they get larger! But a human scaled up to an equivlant height, would be heavier.

So, really tall giants are beanpole thin - makes sense.

Originally Posted by Atgxtg

But the old Giant stats simply give 3D6+6 SIZ per 2m, so old style giants actually get less dense as they get larger! But a human scaled up to an equivlant height, would be heavier.

Originally Posted by soltakss

So, really tall giants are beanpole thin - makes sense.

Or they're made of aerogel. Which they'd have to be, since that much meat and bone would collapse under its own weight. (Except for magic, I guess.)

FWIW, The Book of the New Sun included proportional, "realistic" giants that had to live underwater once they reached a certain size.

Originally Posted by soltakss

So, really tall giants are beanpole thin - makes sense.

Or, as fmitchell jokes, are made of aerogel. The artwork from RQ Vikings would not support the beanpole thin theory.

IMO, it's more of a case of not updating Giant stats in RQ3. RQ2 had several creatures that had stats that scaled based on their length/height, such as the crocodile. You you to see STR and SIZ stats like like 1D6 per 2m or so, and the weight progression for SIZ was fairly linear. But when RQ3 revised the SIZ table, Giant's didn't get stats that increased properly for the new scale. You can see it with the huge spread in the SIZ stat for big giant's. For instance a giant with a SIZ roll 9D6+42 could weight anywhere from around 2 and ahalf to a hundred metric tons. It's hard to come up with any sort of scale with such a huge difference in weight.

Realistically, human leg bones can't support the weight of a man at around the 60 foot height mark, and the other bones give up before that. Muscles would have problems moving that weight, too, as realistically, you only get about 2 points of STR increase (bigger muscles) per 3 points of SIZ. But then Giants are not realistic. I just assume that they are supernaturally strong, and that strength applies to their material strength of their bones.

But for a better, and IMO easier SIZ progression, just add 24 points of SIZ per each doubling of height. I can (and have) done a table based on this that can be used to scale up a human (or other creature) to just about any height. There are problems at the extreme ranges (below SIZ 8 or above SIZ 88) but 99% of beings in BRP fall in the 8-88 SIZ range.

The realistic scaling is actually a key point to a project that Erasmus and I have been working on for writing up stats for creatures. It makes it fairly easy to come up with stats for similar species by scaling up or down the stats from the states of a related species.