@CornBurrito
Seriously, telling others how to play at their tables is a load of crap. Don't do that. If it's my table, my firends, and we decide that it's more fun to play without pants on and covered in Cheetos dust, then that's on us. It would be silly for you to preach to me about how cheetos dust isn't good for my bare thighs, or how all the dust on my fingers will get on the table.
On Caster Fumbles:
If a caster can fumble fail, then they need to be able to Crit also. To me this is the natural balance of Melee vs Caster, melee can crit/fumble, casters get niether, if you want casters to have one then give them the other.
Casters can roll too. Instead of taking a flat DC = 10+spell casting, roll. DC = d20 + spellcasting.
Now your casters have a chance to critical fail, but you need to come up with a rule for their natural 20s. Add extra dice to damage? Make the target auto-fail a save? I don't know, it's a can of worms.
We let casters roll for spell DC in 3.5, but never included crits/fumbles.
On
Save Criticals & Fumbles:
Instead of changing the rules, play within them. Give Criticals & Fumbles to saves that affect the Caster of the spell. Some examples of this:
- I save vs Charm with nat20, a force of willpower so strong that I'm able to charm the caster. He now makes a saving throw or becomes charmed by ME!
- Nat 20 on dex save vs fireball, no damage.
- Nat1 on fireball save, bonus damage!
- Nat1 on Charm save, double duration.
- Nat20 against Lightning, I'm able to decide if it changes direction
- Nat20 against single target spells, the explode right as they are cast causing 1/2 normal damage to the caster.
Fumbles for everyone!