There's a lot of variety in how games handle critical hits and fumbles from simple damage multipliers/bonuses/penalties to DCC style tables with effects that range from yawn inducing to insane.

Fumbles in particular are, I dunno, kinda lame? Hyperborea has a lot of fumbles that are like "you embarrass yourself with a bad miss." Okay, does anyone actually role play that? Most I've seen from this one is a smirk or chuckle.

Then you have DCC crits, with stuff like a Giant literally hammering you into the ground like Wile E Coyote.

A lot of players seem to hate the concept fumbles because they're jarring and penalize martial classes. Perhaps there's something about a natural 1 meaning you did something you didn't intend to do that is insulting to players.

I have a half-baked idea for fumbles. It gives the player some choice, but it's a bit "meta." If you roll a natural 1, you've overextended yourself or left yourself open, and so if the next attack against you hits, it results in a permanent injury. This would be a way of introducing permanent injuries in games that use simple bonuses for critical hits. It's meta because it warns the player that something bad is going to happen. But it also gives the player a chance to withdraw for a round to avoid the effect.

What do you think of this idea or what do you think about crits and fumbles in general? What system has worked well for you?

I stopped using crits & fumbles years ago.   Crits are much harder on PCs than on monsters within the context of the game.  Fumbles if any should be rarer than one in twenty attacks.  They should also not be rolled for but adjudicated by the GM based on total circumstances (this includes the fighting proficiency of the recipient PC) and to add color to the game.

From the 10,000 feet perspective, I think that critical hits and fumbles need to be built into the system to work properly.  I don't mind the occasional "double damage on a natural 20" kind of thing in B/X for example, but when it gets much more extensive than that, I want it integrated.

ArmsLaw/ClawLaw, the early Role Master supplements meant to be bolted on to D&D or other systems is the big elephant in the room against my view, in some ways.  It it bolted on, not built in. OTOH, it's coherent within itself, not merely bolted on, and meant to somewhat replace some of the existing mechanics.

My main reason is that the system has an implied sensibility (or at least a range around a sensibility) and expected math in the mechanics.  The critical system has to take that into account.  It doesn't need to necessarily do exactly the same as before (otherwise, what would be the point?) but it does need to consider various side effects.

At a more granular level, I think it tends to work a little better in practice if critical hits and fumbles are asymmetrical.  I've designed my own system with that in mind, where critical hits are an integrated part of the system math and options.  For example, "great weapons" used with the appropriate training are more likely to do critical hits, and this is an expected part of the balance of the system.  Fumbles, however, come in two flavors:  Edge cases and Extensions of the Critical Hits. 

Edge cases include things like shooting into melee, where normally it's only a minus to hit, but a fumble means you've shot a friend in the back.  Extensions of the critical hits are things such as failing to react/resist to a fall or an area effect spell, where it means for you the fall or spell has now done a critical hit. 

IMO fumbles are usually lame, unless you're playing it for laughs (e.g., DCC or runequest with its invisible turtles)

If a PC fumbles, he looks stupid.

If the PC wins because the villain fumbled a roll, it detracts from the victory.

And, as you mentioned, it is specially insulting to fighters - who usually roll more often (and are outshined by wizards anyway in many systems, although DCC has fumbles for wizards, which is fine IMO).

High level fighters with multiple attacks look particularly stupid, fumbling every few rounds.

I'd occasionally say "nat 1 means something horrible happens" if a PC is trying to do something incredibly risky (e.g., shooting into melee), but not under ordinary circumstances.

CRITS, OTOH, are cool and do not need to be too punishing. For example, maximum damage in B/X, or an extra attack on a nat 20.

They make fighters cooler and monsters scarier.

https://methodsetmadness.blogspot.com/2016/11/crits-are-fun-fumbles-are-funny.html

Here's what we do for the two games we normally play:

Swords & Wizardry
   Criticals are inflicted on a natural 20, then roll another d20:
o   1-15: x2 damage
o   16-17: x3 damage
o   18-19: x4 damage
o   20: x5 damage
   Then roll hit location die and describe your critical!*
   
A natural 1 is a fumble; see below

   Fumble Table
o   1: Damage self for 1-8 hp
o   2-3: Damage self for 1-4 hp
o   4-6: Break weapon; magic weapons get save
o   7-10: Hit nearest ally for normal damage
o   11-15: Drop weapon; lose next round's action
o   16-20: No fumble; weapon slips but grip is regained
   If a PC or foe rolls a natural 1 on a save vs. a damage causing spell, they take a critical as outlined above

*I have a d20 hit location die I got in the Modiphius Conan RPG

Castles & Crusades
   On a natural 20 a critical hit is scored; see table below.  This also applies to spells that require an attack roll to hit. See below.
   Roll on the hit location die & describe your critical
   Fighters and barbarians have higher threat/crit ranges as noted below

Crit Ranges for Fighters & Barbarians
Levels 1-5: 19-20
Levels 6-10: 18-20
Levels 11+: 17-20

Critical Table
1-15: Double Damage
16-7: Triple Damage
18-19: Quadruple Damage
20: Quintuple Damage

   Fumbles occur on a natural 1. Use MERP fumble tables

   Spells fail due to SR or foe rolling natural 20 on save; roll on MERP spell failure table
   If you roll a 1 on a save vs. a damage causing spell you take a critical as above or on appropriate MERP table

I have all the MERP Crit & Failure tables laminated as extra sheets to use with my DM's screen.

These can get pretty lethal, but no group I've used them with has ever complained and we've had some really epic moments both for and against the players.

Hackmaster 4E is famous/infamous for it's critical hit and fumble tables. It's complicated enough that I used an Excel spreadsheet that someone made a long time ago to generate the results

Now? Since I don't run HM 4E anymore, I keep it simple: nat 20, roll damage twice. I don't do fumbles.

Quote from: rytrasmi on September 21, 2023, 11:46:28 AM
What do you think of this idea or what do you think about crits and fumbles in general? What system has worked well for you?

If I had my way, I'd use Arms Law for every game, even if it's ridiculously unforgiving...the results are just too entertaining and funny.

That said, for current D&D game which is really Palladium FRP with some houserules and custom character classes, the combat types already have crits built into them so it's pretty easy to run. Otherwise double-damage on a 20 works. Fumbles on a 1 if the players want to use them, but we have some shared charts we all add to with stupid nonsense. Last game someone else was running and I lost two characters to fumbles, so I decided not to use them for current game.

The best crit rule I've seen is in Traveller; if you succeed in an attack then anything you rolled in excess of the target number gets added to you damage roll.

The only time I use fumble rolls in any game is when the PC attempting the action is trying something outside their skill set that could have serious consequences if they failed.  Then it becomes obvious as to what the outcome is going to be if you don't get it right.   

We'll use or not use them depending on the type of game being run. Fumbles require a lot of on-the-spot thinking, I feel, which means I struggle with them. Also they seldom apply to most casting systems, which almost seems to penalize martials. Like, why is the martial just as likely to drop his sword as a novice wizard is to drop their weapon in pitched melee? Aren't they supposed to be good at that? 

I feel they work well when you want the dice rather than player or character skill to determine outcomes, or when you want the impossible or improbable to feel theoretically in reach, but otherwise, *shrugs*.

EGG pointed out that criticals and fumbles will end up affecting player characters far more in the long run and why he didn't include them in D&D.

Personally, I've had more than one character die by a fumble playing Rolemaster. And Rolemaster is not a quick game to make new characters for. Which is why we stopped playing Rolemaster

Quote from: Eric Diaz on September 21, 2023, 01:39:37 PM
IMO fumbles are usually lame, unless you're playing it for laughs (e.g., DCC or runequest with its invisible turtles)

Pssst, it's Rolemaster with the invisible turtles.

Quote from: JeremyR on September 21, 2023, 06:56:04 PM
EGG pointed out that criticals and fumbles will end up affecting player characters far more in the long run and why he didn't include them in D&D.

Which one of the many reasons I still prefer classic D&D. Low level PCs in classic are already fragile as it is. No need to add splatting them with crits.

I am definitely in the camp that thinks fumbles, as they're usually played, are immersion-breaking in their silliness. I competed in Olympic fencing for over a decade, and have done plenty of HEMA and other kinds of mock battle. I don't think I've ever seen someone accidentally throw their weapon, and I can count maybe a handful of times I've seen someone unintentionally drop a weapon without being actively disarmed. Accidentally hitting an ally with a melee weapon is marginally more common, but not by much. The only way I've seen it happen is if in a chaotic melee someone actually mistakes friend for foe.

I've also can't recall having ever heard or read a historical account of any of these things happening. Though I'll concede I might have.

On the other hand, the idea of a roughly 5% chance of something going catastrophically wrong in in the chaos of battle does make sense to me, so I tend to regard fumbles as something to be fixed rather than discarded.

Apologies if I've posted this before and forgotten about it, but a while back I set out to write my own fumble tables, based on things I felt were more plausible for real combat. I think it started off as me wanting to fix gun fumbles, since I don't believe anyone would use a weapon with a 5% chance of exploding in their face every time they pull the trigger. But it quickly expanded for bows and melee weapons. I've never been totally satisfied with it, especially with the bow fumbles, but I'll post it here in case people find it interesting.

Musket Misfire Table:
1: Blowback! Make a Reflex save or take weapon damage. Weapon is useless until repaired by a gunsmith.
2-4: Bent Barrel! -1 to attack rolls with this weapon, until it is repaired by a gunsmith. 
5-7: Barrel Fouled! Take 1d4 turns to clean it before firing again.
8-9: Forgot to Remove the Scouring Stick! 1:4 chance of recovering it, or else can't reload until it is replaced.
10-12: Broken Flint! Weapon will not fire until the flint is replaced (1d4+1 rounds to replace)
13-15: Clumsy Firing Position! Take 1 point of damage from mishandling the recoil.
16-17: Sparks in your Eyes! Take -2 on all attack rolls for 1d6 rounds.
18-19: Bad Powder! Reload and fire again.
20: No Spark! Weapon can be fired again without reloading.

Crossbow Misfire Table:
1: Broken Bow! Weapon is useless until repaired by a skilled smith.
2-6: Cracked stock! Weapon takes a -2 two accuracy until repaired.
7-11: Snapped your String! Cannot shoot until the bow is restrung (1d4 minutes to replace)
12-15: Broken nut!  Weapon will not shoot until the nut is replaced (1d4+1 rounds to replace)
16-19: Loaded the Bolt Wrong! 1:2 chance to drop the bolt. If not, shoot again without reloading.
20: Wobbly Shot! A crooked bolt flies wildly, dealing one point of damage to a random target downrange.

Bow Misfire Table:
1: Broken Bow! Weapon is permanently destroyed
2-5: It's the Damp! Wet wood makes weak shots. Weapon takes -1 damage permanently
6-11: Snapped your String! Cannot shoot until the bow is restrung (1d4+1 rounds to replace)
12-15: Slap on the Wrist! Hurt yourself with your own bowstring. Take 1 point of damage; Make a Fortitude save or drop your bow.
16-19: A Garish Pincushion! Hit your target, but deal no damage, as the arrow fails to penetrate.
20: What were you thinking! Lost your concentration. Roll another attack against a random target downrange.

Melee Mishap Table:
1: Broken Blade! Weapon is destroyed, and may or may not be able to be repaired.
2-5: Disarmed! Drop the weapon used in the attack.
6-9: Fools Rush In! Unintentionally find yourself grappling with your opponent.
10-14: Overextended Attack! Enemy makes an immediate counterattack at +4 to hit.
15-16: Treacherous Footing! Slip, trip or stumble, and fall prone.
17-19: Clumsy Swing! You look like an idiot, but take no penalty.
20: Take What You Can Get! You missed with the blade, but managed to punch the target with the hilt or handle. Deal 1 point of damage.

Prowlers doesn't have criticals or fumbles at all. The more successes you get, the better you do; the fewer, the worse. And its resolution system encourages players to use their imagination and get immersed in the world, without ever being heavy handed or feeling contrived. I would never trade it for the restrictive clunkiness of a random table.

Quote from: JeremyR on September 21, 2023, 06:56:04 PM
EGG pointed out that criticals and fumbles will end up affecting player characters far more in the long run and why he didn't include them in D&D.

That exact reasoning is why I don't do fumbles at all, barring the 'I try to do something outlandish' choices coming into play.

I use a system slightly modified from Combat and Tactics for damage, but nothing crazy and it's all easy to do during play.

Nat 1 Miss
Nat 20 Hit

Roll Nat 18+ and hit by 5 or more - double damage dice
10 or more - treble
15 or more - quadruple
and so on


It gives a reasonable but not outlandish damage bonus to fighters with a bigger damage bonus the more they outclass the target, and can still be achieved by Clerics/Thieves often, with Mage types still being able to pull it off but not as frequently. Plus no tables to roll on makes it super fast at the table. And yes, it also means that the Clerics, Thieves, and especially Mages might get critted themselves more often than the fighters. I leave it to the players to figure out the tactics to prevent this.