Simple Unpredictable Magic for OSR Gaming

 Okay, so I sort of lied there in the title.  You could use this with almost any game with fantasy magic in it.  I made up these tables to go with Old School Hack/Neo School Hack but then realized you could apply them to plenty of other rules sets. 

One complaint I have always had with D&D, and D&D based games, is the predictability of magic casting.  Sure, there are a few spells where a random roll is involved, but usually the spell is cast and the effect occurs without needing a roll.  This never felt right to me.  Also, certain magic items should become less of a sure thing over time.  Those potions are magical but after centuries or even millennia sitting in a chest in some tomb they might well go bad.

So here are some simple d12 based tables for potions, scrolls, and spellcasting to keep everyone on their toes.


Potions (roll 1d12)
1: Toxic!  No magical effect, but drinker suffers one wound
2: Flat!  No magical effect happens
3 - 11: Shazam! It worked!
12: Mana Rush!  Magical effect works and drinker gains 1 Awesome Point

Magic Scrolls (roll 1d12)
Anyone can read a magic scroll if they know the language it's written in.  In the case of a holy or unholy scroll, the reader must also at least partially share the same alignment as the deity to whom the scroll is dedicated.
1: Rebuke!/Backlash!  No magical effect, scroll crumbles into dust, and reader suffers one wound
2: Mis-read! No magical effect happens but you can try reading the scroll again later
3 - 11: Praise and Glory!/Shazam! It worked!
12: Mana Rush!  Magical effect works and reader  gains 1 Awesome Point

Magic Casting (roll 1d12)
1: Rebuke!/Backlash!  Casting fails, the spell is expended, and caster suffers one wound
2: Botched! Casting fails, but the spell is not expended and you may cast it again later
3 - 11: Praise and Glory!/Shazam! It worked!
12: Mana Rush!  Magical effect works and caster gains 1 Awesome Point

Conversion to typical D&D values:

• for the damage, use 1d4 points of damage per level of the spell
• for the Mana Rush either: add Awesome Points (or Hero Points, etc.) to your game, have the person gain 1d6 temporary hit points, or allow the scroll or spell to be cast normally.