Medieval Naturalism and Science Fantasy

So I've been talking and working within the framework of medieval naturalism, where magical thinking is correct and spontaneous generation is a real thing. The science of this world is alchemy and the study of magic, not the laws of physics as we know them. This is going to be the main theme of Demon-Haunted Lands, bringing this approach to fantasy gaming, from the dungeon to the nine hells, from good and bad luck to the faerie realm. So that's one part of the game.

At the same time, I love science fantasy elements. I reprinted my Death Ray article in Dungeon Crawl #2 because I thought it was the kind of element worth sharing. This works together with the concept I discussed in February's series of posts on the planes as planets. Specifically, every plane has its own laws and reality works accordingly - for instance, on the science fantasy Mars, death rays can be manufactured, but on the alchemical / magical Earth, they couldn't be reproduced even if you landed the Martian factory in a space ship. The death ray itself works, but should have some chance to malfunction.

One of the consequences of this is that the Earth is actually a heavily magical plane, and by contrast some of the other planes such as Mars, Venus and the Moon are relatively low-magic. This impacts characters who travel between them and attempt to adventure there.

The biggest difference is that magic does not work well. There is a chance of spell failure, although items are less likely to malfunction than memorized spells. Characters simply cannot memorize as many spells and lose a certain degree of effectiveness. This is offset, for instance, by an increase in strength on Mars due to reduced gravity, but a sword +2 is as out of place on Mars as a ray gun is on Earth.

Adventure on the Martian plane or beneath the clouds of Venus, then, follows its own rules. In further realms, such as Jupiter or Yuggoth, the rules are stranger and more bizarre. After all, the great ordered storms of Jupiter are home to massive sky-dragons and megalithic cities floating above the storms. In Yuggoth the geometry is wrong, perhaps to the point that it would distort a human's perceptions like M.C. Escher's paintings.

One major conceit of Demon Haunted Lands is that this is also true of Hell and Faerie, the realms described in that supplement. In Faerie the world is extremely beautiful but also chaotic - there are a few places where it is anchored and prevented from going into the bland sameness that Moorcock warned would be the result of too much chaos. Hell, on the other hand, has a duality; on the one hand it is a vast and empty underworld, on the other it is a pit of fire and demons and lost souls.

I think this cosmic vision of "different plane=different rules" works much better than trying to establish an easy one-size-fits-all magic.