I sometimes feel like I'm the only OSR guy that doesn't have Dungeon Crawl Classics. I've gotten some modules for it, but don't have the game itself. I've of course heard about the spell system, where every spell has a random table to go with it.
What I'm proposing is a bit different from my perception of DCC's spell system, but somewhat similar. I'm not sure how well this would work in play, it's just a random idea I had. But enough blather, what was my shower thought last week?*
So, using a TSR version of D&D, or a retroclone of the same, here's an idea for Magic-Users (I probably wouldn't allow it for Clerics, but then again, maybe I might) that might give them a bit more oomph. Once they've cast all of their prepared spells for the day (or if a situation calls for a spell in their spellbook but not prepared), they can cast it, but need to make a roll using the Chainmail spell chances (2d6 rolls) to see if the spell goes off or fizzles.
Probably too powerful if it's just "cast or fail" so (like DCC) it would need some chance of misfire of some sort (Wild Magic tables? Reverse effects or targets? Page in the spellbook is burned and the spell is lost?) to make it a gamble to keep casting spells when you've exhausted your spells per day or are casting something you didn't prepare. Higher level spells would also incur a higher chance of a negative effect besides just not casting the spell.
It might be fun to try this some day.
*Or was it 2 weeks ago? I'm so behind on blogging. We've had two sessions of Dean's game that I haven't posted about. I've also been doing the West Marches for 2 months now, and it's going well. Chanbara is nearly ready for publication. And I've seen a movie or two I could review. No time for any of that recently.