As I've stated before, I'm a really big fan of the OSR game Shadowdark, and I really enjoy how it blends old school with newer resolution mechanics.
The
only thing I don't connect with well is Shadowdark's magic system.
Shadowdark uses a roll-to-cast system where a success means the spell
works and a failure means the spell does not work and cannot be cast
again until after a night's rest. Rolling a 20 results in a better than
normal cast, while rolling a 1 results in a disaster for the caster.
Many people love this kind of dangerous and wild system, but I am not
one of them.
I have always favored Vancian Spell Slots since I
was introduced to them way back in my AD&D days. A famous fantasy
writer once recalled first reading the original D&D rules for spell
slots and believing this would be perfect for his fantasy world, which
itself eventually became a popular campaign setting. He explained that
it gave concrete rules for how many spells a wizard actually had each
day. This magic, while limited, did something for his setting that
nothing previous did for magicians - it grounded them in a way where you
could imagine yourself as one. This is what I like about Vancian magic
and why I decided to bring it to Shadowdark.
Vancian magic was
inspired by the writings of Jack Vance in his Dying Earth series. The
idea is that a magician collects their spells into various ways, but can
only store so many of these magical patterns in their mind each day for
use. A magician may possess many spells, but must carefully choose
which to bring with him or her on their adventure. As the magician casts
their spells, they “release” the patterns stored or memorized in their
minds and must rest before being able to cast them again. This is the
basis of Vancian magic, sometimes called “fire and forget” magic.
Anyways, that's something that's always appealed to me as a GM and as a player. To that end, I have created a guide on how to convert Shadowdark's magic system over to Vancian spell slots. There are two methods presented in this guide, one using the OSR spell list and the other explaining how to convert the Shadowdark spells themselves, which is far more time consuming but rewarding.