"I think Hydrogen is a rare element" and other science facts.

[Willie the Duck]

Hmm. In my experience, the obvious stuff (FTL travel, magic making/destroying matter, no guns alongside plate, artificial gravity, squared-cubed laws and giant fantasy creatures, open-topped castles in a world with griffons, etc.) usually gets called out as part of those "save where noted." It's often subtler stuff or downstream consequences that get missed.

Stuff like implied climatological consequences. Huge mountain ranges won't create a desert on one side. Rivers will flow in whatever direction was needed at the time (and of course comprised of sixty-degree turns if the world was initially constructed on a hex map). And so on.

Or a sci fi setting where slower-than-light travel is done with perfected cryo sleep. The crew will get out of their sleep pods and go to the galley or cargo hold and pull out something that by all rights would have decayed/discharged in the intervening years and it is perfectly ready to use.

Generally speaking, I don't have a problem with a lot of these. I get it. It's conservation of story prompts, and generally we (my groups at least) are looking for 'just like the world you know, but with ________' and not the perfectly realistic and exhaustively detailed rebuild of the world with all the holes filled in. Every once in a while, though, there's a 'you did not think this through' moment that jars everyone.

 

[Micah Sweet]

Well, if J.J. Abrams was in the helm they might...

Can I use the funny and sad responses at the same time?

 

[James Gasik]

Magic creates energy and matter out of nothing, meaning that the gameworld is constantly adding both to its (locally) closed system. I’m not a scientist so I’m not sure what would happen, but I’m pretty sure it would be bad.

So I had a conversation about this once. We were discussing common, expensive material components for spells, ones that have set prices. 100 gp pearls, diamonds and diamond dust, that sort of thing. If there components are consumed by casting (as happens in many versions of D&D), what happens when, you know, the world runs out of them? Even though pearls are grown, there can't be that many of the right price. Or does inflation and local pricing matter? Does Identify require lesser pearls in the desert than it does in a sea town?

Do diamonds automatically replenish themselves, perhaps due to some rift to an elemental plane? Do the Gods do it? Will prices or even components change over time? Are these things bought and sold in a "mage marketplace"?

And what does happen if an enterprising Wizard opens a Gate to the Elemental Plane of Earth and negotiates with the Dao for gems in bulk?

 

[James Gasik]

An acquaintance was playing in a supposedly semi-realistic SF campaign, where they landed on the Sun. Until he had a quiet word with the GM.

There are plenty of people around who think they learned about the realities of space from Star Wars and/or Star Trek.

I remember reading a science fiction story about a mining colony on the surface of a star that had grown so cold that it had a solid surface. You'd still burn yourself if you sat still though. Not sure how realistic that would be, though.

 

[James Gasik]

I doubt either franchise would make that mistake without one heck of an explanation.

How about a planet with a core of liquid water?

 

[kigmatzomat]

I remember that KoDT strip. B.A. was miffed at Brian's directing the group's starship through a nearby planet to skim some of its atmosphere (or was it water, I can't remember now) and have the ship's processors separate out the hydrogen molecules, which was what powered their engine.

Yeah, science fiction has the issue of "science" right in the title. If you aren't a science-y person and you pose a science-y problem, be prepared for science-y people to mess you up.

This is like running a social based game while a player is an actual diplomat.

I can "scifi" that into "you need metallic hydrogen which your ship can't manufacture" or "Make an engineering roll....7? Ooh, looks like after conversion losses, running the processors, maneuvering in a gravity well, etc, you will use more fuel than you can make. Too bad you didnt upgrade the ship system to Tech Level 5 back at Phobos and instead got that grav-lance"

 

[Laurefindel]

Getting all your science facts straight when doing sci-fi is hard. I’m ok to assume a good part of fiction in my science-fiction, but I prefer when the science part is hand-waved rather than explained.

Gas tends to have a low molecule-to-volume ratio and density at normal pressure. I’d have less issues accepting that hydrogen gas exists pure in the atmosphere of a planet than believing that scooping some without some process of pressurization and liquefaction would result in a lasting reserve of fuel. But if a GM just tells me “you can refuel your ship by scooping the atmosphere of certain planets with the right gas composition, because hand-wavium technology”, I’d accept it.

 

[monsmord]

One of our long-time group decided to homebrew a fantasy game and DM (3.5e) for the first time, after decades as a player. Our party was underground and...crossed a river...of lava...on a rope bridge...that had been there for...a long time? Sure, this wasn't meant to be science fiction. Also, not science.

 

[Lord Shark]

How about a planet with a core of liquid water?

Or humans devolving into giant salamanders after going above a certain faster-than-light speed.

 

[James Gasik]

Or humans devolving into giant salamanders after going above a certain faster-than-light speed.

Hey that didn't happen, and if you remember it happening, you're from an alternate timeline!