An atla (mayan spear thrower) might give a javelin enough oomph. But I'd say it requires a dex and str. So if you roll for random stats mods....

...take your creature's base stats and roll a d4. 1,2 is minus 1 or 2. 3,4 is plus 1 or 2 respectively.

...then if your kobolds dont meet +1 to both they can't use it. If they dont have +2 to both they take minus 2 dmg. If its +1/+2 then its minus 1 dmg.

Quote from Brotherbock >>

Sweep attack is an interesting idea, I think that could be developed into something. Damage Threshold, I'm not sure at the moment why you wouldn't just use Resistance, as an already existing mechanic. Give giants resistance to bludgeoning and you may be set. Consider--if the kobolds were throwing daggers, would it seem so absurd? 

Of course, one thing to consider as well is that thinking of sling bullets as 'tiny rocks' does a slight disservice to the sling as a weapon. https://www.youtube.com/watch?v=_1oeZQH4oEc

 

 Slings were absolutely murderous.

But they are probably too big for kobolds to use against anything but small game.

I think I did the "random stats" wrongly. Probably would look like this.

D20: 1=+2, 2-3=+1, 4 thru 17= 0. 18-19 = -1, 20= -2.

That gives you a bit of a deviation from the average.

Quote from IDNeon357 >>

 

Kobolds with slings might find it difficult though to get enough force from a shorter sling which is necessary to be swung around by a more diminutive creature.

Probably would say a kobold could do -1 damage with a sling.

Although the MM gives kobolds a +2 to their sling damage. 

The thing about a sling is that you don't have to be particularly strong to take advantage of it. Rotational speed is something you can build up without needing a lot of strength. I agree about the bow, that's more sheer arm strength required. But you give a sling to an 8 year old and she can do some damage (if she hits, but that's coordination, not strength). A kobold should be able to generate most of the rotational speed that a stronger creature can. That's also why the sling length wouldn't have to be all that much shorter. The kobold itself is short, but a 3 foot kobold could still make use of a 2 foot long sling. That's a lot of torque, and with good technique, the weaker kobold could still handle it.

Is it too late to joke about how sensible an ogre actuary would act?

 Woot! Look at all these great responses! I'd reply to everyone individually, but that would clog the forum.

I am seeing some common patterns that are really helpful in refining my ideas.

1). Just don't let the Kobolds swarm our poor Giant, get some intimidation involved, get some terrain involved!

• This is really good in terms of keeping everything the same and making the Giant feel bigger and badder without actually messing with the game. The only problem is that I'm running knee deep into an army scenario. I've got a goon squad of 12 giants charging a platoon of 400 Kobolds. Now I've made a totally different list of rules (much simpler than the UA Mass combat rules) for that kind of combat, but there is no reflection of that in the creatures normal stat block. 

2). Give the Giants resistance to physical damage!

• Simplicity is key and resistance would be a great boost to the feel of the giants! Versus a party of adventurers this is a fantastic idea to make any foe, giant included suddenly nastier. But resistance is too easily countered by mass numbers, that still make the giant feel in my opinion squishy in an army style scenario. Can I offer an extreme? Who wins 1 Tarrasque the greatest monster in DnD, or 10,000 peasant archers with longbows with a +5 to hit who deal 5 Damage each? Mathmatically, the archers, nearly every time. 10,000 archers fire, approx 500 hit (rolling 20 on d20, ignore crit).  500* 5 damage = 2500 damage, that's ~ 4 times the health of our poor Tarrasque. And sure, the Tarrasque is immune to all non-magical damage, but all you need is to give every archer a single +1 magic arrow. And of course, you can just not do that, but its beside the point. Due to DnD's base system of AC and HP, there greatest weapon is massing numbers, death by poking, unless there is a way to ignore small and meaningless amounts of damage no matter the source.

3). The "Mob" Rule

• This idea is molto bene because it carries the flavor of the sweep attack rule I came up with, without much extra weight. I feel like this would work very well. The only problem is that I couldn't carry it over to any fight I had between a giant and adventurers. It would feel very cheap and probably ruffle player feathers in a bad way. The sweep attack idea I think better transitions the idea of the mob rule into the adventurer zone without changing to much in the game.

All in all, I'm still interested in hearing more thoughts! Thanks to everyone so far. :)

Maybe y'all are just playing the wrong game for what you want?

Quote from Wysperra >>

Maybe y'all are just playing the wrong game for what you want?

 Maybe you just describe in more detail what you are talking about

There are games like GURPS or Fantasy HERO that have built-in mechanics to deal with the difference between hitting a creature and being able to damage it. I'm not sure if GURPS has a difference between Stun damage and Lethal damage - it's been too long. Both systems also include hit-location damage modifiers.

Example: kobolds might fire a bunch of arrows or rocks or whatever and some hit the giant. However, the combination of the giant's thick skin and hide armor, prevent most if not all of the damage.

After modifiers for the kobolds attack score and the giants defense score, the kobolds need 8 or less to hit

10 , 10 , 4 , 9 , 4 , 11 , 6 , 16 , 9 , 12

One kobold hit, he rolls damage against the giant's 5 armor 2

Even though he hit, the amount of damage he did wasn't enough to get through the armor.

Quote from Wysperra >>

There are games like GURPS or Fantasy HERO that have built-in mechanics to deal with the difference between hitting a creature and being able to damage it. I'm not sure if GURPS has a difference between Stun damage and Lethal damage - it's been too long. Both systems also include hit-location damage modifiers.

Example: kobolds might fire a bunch of arrows or rocks or whatever and some hit the giant. However, the combination of the giant's thick skin and hide armor, prevent most if not all of the damage.

After modifiers for the kobolds attack score and the giants defense score, the kobolds need 8 or less to hit

11 , 13 , 7 , 10 , 9 , 13 , 13 , 9 , 9 , 12

One kobold hit, he rolls damage against the giant's 5 armor 2

Even though he hit, the amount of damage he did wasn't enough to get through the armor.

WEG's d6 system was nice. You have a Strength ability which allows you to roll a certain number of dice for Strength feats and activities. The stronger you are, the more dice. So having 6D in Strength let you roll 6d6 to knock down a door.

But strength was also your resist roll for damage. So you determine if you get hit (attack roll vs dodge roll). If you get hit, the attacker rolls damage dice. You roll your Strength dice. If you roll higher, you are not injured. If the attacker rolls higher, you subtract your STR roll from the damage roll and you take the remainder in damage. 

But I think you have a point (and again as a caveat, houserule away if you have more run with new rules :) that D&D isn't designed to be that complicated. HP are supposed to represent a combo of bodily health and fitness. The giant getting 'worn down' by fighting all these kobolds is part of the HP/Damage setup in D&D. Even if the sling stones don't do much (which they would...they really really would, but I've already made that point), the giant is going to get worn down fighting a horde of 3 foot lizards. That is HP loss. Even without a single bleeding wound.

So D&D is meant to be simple, the simplicity is intended to be a feature, not a bug. And again, if you think it's not realistic, mod away. I mod falling rules in every game I run simply because the RAW on falling is wildly, laughably, ludicrously unrealistic, to the point that it actually affects my enjoyment of the game. But if you find yourself modding away until you're left with something very different, a different system to start with might be better.

That said, I just don't think it's unrealistic for a bunch of kobolds to beat a giant. Slings are nasty weapons, you don't need to be super strong to use one effectively, and it's plausible for the less agile giant to not be able to attack more than one or two kobolds in a round. I mean, I could kick the crap out of any 7 year old. Four or five of them, even. (blows on fingers) But 20 7 year olds, armed with rocks?