I've recently found a fan made supplement for OD&D ("The Age of Conan" by Jason Vey) that provides rules for playing a Conan/Hyborian Age campaign with OD&D (it's been out awhile, and many of you may already know of it, but ... it's new to me). It really is most excellent, and I recommend checking it out if you haven't yet (and it's companion volume ... "Age of Conan II: Age of Acheron" ... both found here: http://www.grey-elf.com/). So, within the main volume is laid out a magic system, based on OD&D "Vancian" magic (of course), but adding the concept of Corruption. When I read this section, I was gob-smacked! I immediately thought, "this is exactly what I've always wanted for my magic/spellcasting in AS&SH!", for me, it's a perfect addition to the setting ... and one that I think adds the perfect dark overtone to spellcasting ... it's dangerous. I've cherry-picked the parts from the system I feel are most appropriate (I.e: I'm not using the system exactly as-is), and it works like this: When any Spellcaster casts a spell of any kind (and this includes Magicians and Clerics and all sub-classes), they must make a Saving Throw against Sorcery (Spells), if they fail the Saving Throw they gain a Corruption Point (CP). For every five CP's gained, the caster suffers -1 (cumulative) to future Spellcasting saves. Additionally, If a Spellcaster rolls a natural "1" on their Saving Throw, they suffers "backlash" and take 1d4 points of damage, and lose access/the ability to use that spell for 24 game hours. For every five (5) CP's the Spellcaster gains they also begin to exhibit physical effects of their dabbling with darker powers (per the "Age of Conan" rulebook ... "...These effects are up to the GM, but they should include things like glowing red eyes, jet black or scaly skin, an aura of corruption that makes those around him uncomfortable, causes plants to whither, food to rot, etc.,vestigial tentacles, clawed hands, gaunt appearance...the options are nearly endless."). I have not actually put this into play yet, but am excited to try it out with my group asap to see how well it works, to see if it adds the effect I'm hoping for. I'd love to hear any feedback on this you may have, and/or anyone else's similar ideas. Thanks gang!