Genetic engineering has more of an impact on medieval fantasy campaigns than science fiction campaigns.

Genetic engineering has more of an impact on medieval fantasy campaigns than science fiction campaigns.

Yesterday, I DMed a one-shot game for a bunch of friends of mine. This was an interesting game to run for two reasons. First, unlike, my usual gaming buddies, all five of my players were totally new to the game. The most experienced among them had played D&D once before, over a year ago. Second, and perhaps more importantly, all five of the players were colleagues of mine. It's a curious thing, having a bunch of physicians, some of them with PhDs too, sitting around a table and pretending to sneak through a goblin village in search of a marauding weresmilodon. Playing with this particular group was different from my usual in some small ways -- we went though a certain amount of scotch instead of beer, for one thing -- and one big way: I was nervous. Don't get me wrong, I wasn't nervous about my ability to run a game, or my ability to draw them into the story, or to get my laughs and my screams at the right moments. Actually, I was afraid that I'd get called out on bad science. You can't have a medieval fantasy story that's scientifically plausible, certainly not once you have weresmilodons involved, and I wasn't sure if these players would know how to suspend their disbelief the way a more experienced player can. Unsurprisingly, my concerns were unfounded, and nobody gave me any sort of hard time, although after the game, I did exchange a few fun emails with a player or two about the plausibility of some of the magic. Those emails got me thinking about how wizards and clerics are out there routinely rewriting people's very DNA with careless impunity and at surprisingly low spell-levels.

Consider the basic spells from the SRD. In theory, spells that directly alter the body tend to use up a lot of magical power. Consider how high-level a caster has to be to access meaningful healing spells, or to cast Restoration, and you'll see that it actually takes a lot of power to make even theoretically simple repairs to the body. In contrast, there are some spells that make incredibly complex changes to a living body, changes that are infinitely more complex than closing a wound, at low levels. My favourite example has always been Enlarge Person, a first-level wizard spell which actually wreaks tremendous having on the laws of physics. Let's entirely disregard the laws of conservation of mass and energy, since magic clearly isn't limited by those when it comes to summoning spells and such. Instead, ask yourself: how does an enlarged character breathe? See, essentially every process in the human body actually depends on two factors: whether a molecule, ion, or protein is the right shape, and whether it's the right size. The hemoglobin in your blood is able to carry molecules of oxygen because the heme molecules are precisely the right size and shape for an oxygen molecule to attach strong enough to stick, but not so strongly that it won't come off. If an enlarged creature just magnified in size, it would no longer be able to carry oxygen in its blood, and the same logic holds true for pretty much every other biological system. Logically, an Enlarge spell can't simply make all of a creature's cells larger. It must actually create new cells, instantaneously and flawlessly. Miles and miles of perfectly configured nerve cells which miraculously still conduct impulses at the same speed. Miles of blood vessels made longer and tougher, but not actually any thicker, or else nutrients wouldn't diffuse through them. It's magic that's orders of magnitude more complex than any Regeneration spells, and quite possibly more scientifically improbable than things like flight or telepathy or a fireball.

Let me give you another example: the ever popular Polymorph, a mid-level spell. This spell allows a caster to transform their physical body into a wholly different form, taking in that form's physical abilities without altering the target's mind. This is no mere illusion, but an actual physical transformation. Just imagine how much spell power it must take to completely change a creature's entire body into a vastly different form, and somehow make absolutely no changes to its mind, even though the new form's brain might be thirty ounces lighter, or five pounds heavier, or in the case of things like oozes and plants, entirely gone. It gets even weirder, though. Consider that, from years of canonical writings, we know that dragons and devils and other creatures are constantly taking on the shapes of other creatures and impregnating creatures of that type, meaning that the new form must be a fully functioning organism, even if only for a limited duration. It's only stranger when you consider that those shape-changers sometimes pass on some draconic or demonic (or whatever) genes to their offspring, meaning that the spell hasn't simply created a living organism, but some sort of viable hybrid. All of this is accomplished for less magical energy that it would take to cast a spell which simultaneously cures a disease and heals one hit point of damage. It goes without saying that a lot of the same issues raised by Polymorph are also raised by an even lower level spell: Alter Self.

I love bad sci-fi and horror movies, but when I watch them, I have to force myself to turn off the part of my brain that takes note of things like, you can't see a hormone through a microscope, or that humans use 100% of their brains and a good size chunk of the rest of their body to supplement it. When it comes to gaming, I'm comfortable explaining away a lot of stuff with the words, "it's magic, it doesn't have to make sense." I can't help but feel, though, that there are some wonderful story opportunities, if an evil cleric ever catches on to discrepancies like this and finds a way to exploit them ...

More than four years ago, Dr. Eris Lis, M.D., began writing a series of brilliant and informative posts on RPGs through the eyes of a medical professional, and this is the one that appeared here on July 27, 2014. Lis is a physician, gamer, and author of the Skirmisher Publishing LLC OGL sourcebook Insults & Injuries, which is also available for the Pathfinder RPG system.