Cheap ways to reduce a character's weight (but not size?)

[ShurikVch]

Lords of Madness at least implies it: there's an advanced cloaker with the shadow template in that book. Regular cloakers are 100 lb and Large size, so one advanced to Huge should be 800 lb instead, but instead it's only 400. The best explanation for the weight difference comes from the template.

Do you mean +1 size is X8 weight?
But it not always works like that:
Barghest (Medium) is 180 pounds; Greater Barghest (Large) - 400 pounds
Stone Golem (Large) is 2,000 pounds; Greater Stone Golem (Huge) - 32,000 pounds

[Inevitability]

Do you mean +1 size is X8 weight?
But it not always works like that:
Barghest (Medium) is 180 pounds; Greater Barghest (Large) - 400 pounds
Stone Golem (Large) is 2,000 pounds; Greater Stone Golem (Huge) - 32,000 pounds

The default (which I think we agree on) is that each size increase is x8 weight, as implied by Enlarge Person spells and size rules.

For the greater barghest, I'd argue that some kind of supernatural transformation has taken place, and we can no longer assume that it's the basic barghest's body plan but upscaled. The greater stone golem is a bit weirder, as it's explicitly said to 'resemble a typical stone golem in all respects' and I admit that I have no idea what's going on there: perhaps it's someone not thinking the rules through, or perhaps in a rare display of defiance to the square-cube law the golem's interior must consist of denser material to retain integrity as it's scaled up.

That said, my point is that with the cloaker there's no clear explanation for why its weight is only 400 lb, outside of the Shadow template. Just because some monsters seem to defy the default rules for weight and size doesn't mean that all of them will by default do so, or that arbitrary breaks from this pattern are the most likely explanation when we have a potential reason right there.

[ShurikVch]

The default (which I think we agree on) is that each size increase is x8 weight, as implied by Enlarge Person spells and size rules.

For the greater barghest, I'd argue that some kind of supernatural transformation has taken place, and we can no longer assume that it's the basic barghest's body plan but upscaled. The greater stone golem is a bit weirder, as it's explicitly said to 'resemble a typical stone golem in all respects' and I admit that I have no idea what's going on there: perhaps it's someone not thinking the rules through, or perhaps in a rare display of defiance to the square-cube law the golem's interior must consist of denser material to retain integrity as it's scaled up.

That said, my point is that with the cloaker there's no clear explanation for why its weight is only 400 lb, outside of the Shadow template. Just because some monsters seem to defy the default rules for weight and size doesn't mean that all of them will by default do so, or that arbitrary breaks from this pattern are the most likely explanation when we have a potential reason right there.

The X8 increase is less common than you may expect (heck, even Giant Size spell doesn't specify your weight change)
From the Monster Manual III:
Cadaver Collector (Large) - 4000 pounds; Greater Cadaver Collector (Huge) - 15 tons
Shadesteel Golem (Medium) - 1500 pounds; Greater Shadesteel Golem (Large) - 4000 pounds
Siege Crab (Gargantuan) - 30 tons; Greater Siege Crab (Colossal) - 130 tons
Ssvaklor (Medium) - 120 pounds; Greater Ssvaklor (Large) - 400 pounds

Or let's look in the different books
Dusk Giant (Heroes of Horror): Least (Medium) - 300-400 pounds; Lesser (Large) - 600 pounds; Greater (Huge) - 4000-12000 pounds
Kruthik (Miniatures Handbook): Hatchling (Small) - 30 pounds; Adult (Medium) - 250 pounds; Greater (Large) - 2000 pounds

As you can see, the "X8 weight" isn't that safe of presumption - while some creatures, indeed, stick to it (more or less) - like Cadaver Collector or Kruthik - others are very far from those numbers: say, Lesser Dusk Giant should be heavier than Greater Dusk Giant would ever got...

[loky1109]

ToM don't have Shadow Creature template - it have Dark Creature

My mistake. I was AFK in that moment, of course it's Dark creature.

[Sirperry]

Cut off all those pesky limbs. You'll also save all that time you used to spend trimming your nails!

Seriously though, character weight is fluff, change it if you want. Heck, reduce it gradually if that makes you feel better and say you went on a diet.

[GreatWyrmGold]

You wouldn't even need to Alter Self into a different race, just a lighter version of yourself.

Why diet when you can get the same effect from a 2nd-level spell?

Having five hit dice but your hit points remaining the same seems like it could be dangerous at higher level, when Power Word spells begin to come online.

Even if the spell affected your effective HD, power word spells are A. rare and B. have effects based on HP, not HD.

There's a Weightless Scabbard (AEG p.138) but it only makes your weapon weightless, and only while it's in it, and it costs 1,600GP.

...I get why that would be comfortable for the character using it, but why would a player ever want to spend 1,600 gold on that?

Do you mean +1 size is X8 weight?
But it not always works like that:
Barghest (Medium) is 180 pounds; Greater Barghest (Large) - 400 pounds
Stone Golem (Large) is 2,000 pounds; Greater Stone Golem (Huge) - 32,000 pounds

To me, it makes sense that advanced creatures wouldn't octuple in weight. Presumably, most creatures that can grow to a larger size category are near the top of their size category, and grow into the bottom of their new size category.

And then there's the stone golem. I'm pretty sure someone just fumbled a *2^4 where they should have typed 2^3 and didn't think twice about it.

[MornShine]

Have you heard the good word of a Permanent Mark of Buoyancy?

[Beni-Kujaku]

The default (which I think we agree on) is that each size increase is x8 weight, as implied by Enlarge Person spells and size rules.

That is the case when exactly doubling in size. But going up a size category doesn't always mean doubling. Goliath's Mountain Rage says you only gain one foot of height, but you still become large. If the Barghest is 6ft long for 180lbs, and it gains 2ft when becoming Greater, than means it is 8ft long (pretty firmly in Large category), and its weight increases as 180*(8/6)^3~180*2.3~420 lbs, which fits the given figure.

A stone golem is 9ft tall and a greater stone golem is 18ft tall, but the greater one might be slightly more massive, say, 40% wider, which would explain the *16 instead of *8.

[Jack_Simth]

Have you heard the good word of a Permanent Mark of Buoyancy?

Oh. Floatstone. Get enough of them at sufficient caster level, and you can make a flying ship. Well, the equivalent of a hot air baloon, anyway. You'll need more to make it behave as a blimp.