I was wondering if anyone has a house ruling or official ruling for critical fumble?
I think rolling a natural 1 should implicate something more than a simple automatic miss, but all the tables I found on the web are way too complex to add to an already complex game IMO. I don't care for zounds of complexities for every number you roll on a d% like what I found.
I am looking for something that is as simple as it is flavourful to add to the natural 1 in combat.
I do it when my players get a natural 1 for skills and it is always a lot of fun, especially when they get a 1 for their percep roll and see things that aren't there, for example.
The best advice is to "do whatever makes you and your group have the most fun."
Also, you can only auto-succeed or auto-fail or attack rolls and saving throws, not skill or ability checks. According to the rules, anyways. This prevents silliness like a person with -6 stealth having a 5% chance to successfully sneak past the ancient tomb guardian with +20 perception.
Any optional rule that you add to your game is going to add additional time to gameplay. If you really think that a particular fumble or crit should do more than auto-miss or do normal crit damage, then you are perfectly free to add that in as a DM. I recommend against most rulesets that currently exist for such things, though. They end up causing more harm than good, in my experience.
red i like to use fumbles and here's what we do for ours, just roll a percentile and use these results.
1-25 = miss
26-50 = drop weapon (unarmed or natural attacks = fall prone
51-75 = attack ally (you reroll an attack against an adjacent ally still having to hit their ac, and still able to crit them)
76-87 = attack self (you roll an attack against your own flat footed ac.)
88-95 = break weapon (weapon gains the broken condition)
96-99 = confused (player loses their next turn.)
100 = roll twice on this table.
Simple thing we did is if you roll a 1, roll again. If the confirmation roll would also be a miss, then the player must spend a Move-Equivalent action to be able to attack with that weapon again.
Players are encouraged to think up creative reasons to describe why. It could be a dropped weapon, or maybe you got it stuck in the wall behind your target, or maybe you shake your hand in pain after punching the column by accident. The description can be anything as the only game mechanic effect is losing a Move action to be able to use the weapon again.