Troll Lord Games

I'm sure this has been asked before. But I'm really putting this to thought. What would need to be altered to make 3D6 work for combat rolls? And possibly skill rolls? Some higher ACs would be a lot harder to hit I'd imagine. And having 18 the target number for secondary TN would be really rough.

It has come up before. Maybe start here.

The only thing I can think of right off would be the curve. 3d6 is a bell curve - unmodified results would hover around the average. Even though the average die rolls are 10.5 for both methods, the majority of the 3d6 rolls will hover in that area, where as when using a d20, you have a just as good a chance rolling a 1, as you do a 10, as you a 20. Consider a 6th level fighter. If you're rolling about average (we'll say 10) every time, then you're looking at static rolls of about 16. Again, a 16 is the average roll on a d20, modified by +6, but the extremes are a lot less likely. Crits and fumbles are a lot less likely (assuming 3 is a fumble and 18 is a crit).
High TN's become really hard and low TN's become TN's become really easy. For example, under the 3d6, a TN of 16 is only achieved 5% of the time, where in d20 it can be succeeded 25% of the time. Likewise, a TN of 6 is made ~95% of the time and in d20 it'll be possible 75% of the time. So if you want mundane tasks to be mundane and epic tasks to be epic, the 3d6 method is good. There is some information on the d20 SRD that may be of use: http://www.d20srd.org/srd/variant/adven ... eRolls.htm

With 1d20 every number has an equal possibility of appearing. With 3d6, 11 will come up more frequently than 3 and 18.

Traveller uses 2d6 plus modifiers for combat. On a roll of 8+ you hit. Utilize a similar system in Castles & Crusades and you'll likely do well. For Castles & Crusades though, since you're using 3d6, the TN would be 12+ to hit instead of 18+. That 12+ assumes the attribute is not a prime. For a prime, you might want to use 8+ rather than 6+, but that's up to you.

Don't know how deep you want to get into it or what kind of probability/statistics background you have, but you might read this:

http://www.darkshire.net/jhkim/rpg/syst ... otive.html

and look at this program:

http://www.semistable.com/dicelab/

Which lets you play with different die combinations and shows distributions.

A 3d6 system makes minor adjustments like a +1 or -1 extremely powerful. That's not a bad thing in itself.

If I were to do this, I'd take from the attribute charts and change the base TN to 16. That means, without bonuses, you need at least one 6 to succeed.

Allow me to suggest using 3m20, which is to say, roll 3d20 and take the middle value. It creates a nice looking curve from 1 to 20. http://anydice.com/program/4fe has the different charts (I suggest clicking the Graph View for the resultant curve). And this page compares 3m20, 3d6, and 1d20 all at once.

I used 3m20 in a recent Dragon Warriors game (which is a d20 roll low mechanic) and it worked really well. The 3m20 graph is a lot smoother with less of a peak that you'd get from 3d6... plus the bonus of not needing to re-tool TNs so much.

I can also say that I originally balked at the concept of how fast reading the middle value of 3d20, but in practice it was really fast for my group.

Okay, after reading that d20 SRD on 3d6, I think I'm sold. As some of you remember, I hope, I was planning on using 2d6 instead of d20. The biggest hurdle would be making sure I don't have to recalculate everything.

This was what I came up for as Bonus to Hit for the various classes:

Fighting Men: +1 to hit lvls 1-3, +2 to hit lvls 4-6, +3 to hit lvls 7-9, +4 to hit lvls 10-13, +5 to hit lvls 14 and up
Holy Men: +1 to hit lvls 1-4, +2 to hit lvl 5-8, +3 to hit lvls 9-12, +4 to hit lvls 13 and up
Rogues: +1 to hit lvls 1-5, +2 to hit lvls 6-10, +3 to hit lvls 11 and up
Magic-Users: +1 to hit lvls 1-6, +2 to hit lvls 7 and up

Since I use a fusion of AD&D 1st Edition and C&C, I go with a modified form of 1st Ed. Strength bonuses:

12 = +0 to hit, +0 damage
13 = +0, +1
14 = +1, +2
15 = +1, +3
16 = +2, +4
17 = +2, +5
18 = +3, +6

Thanks every one for the reply. I'm still mulling this over. Two reasons I was thinking about using it. And Why I wanted it over a 2D10 system or any other die type. Besides the fact that I really like bell curves. Is I have really grown to love the stunt system from the Dragon Age Rpg and was thinking about using it for an up coming game.

For those not familiar with the stunt system ill try to explain.
You roll 3d6 with one die being a different color. If any of the die come up doubles and the roll was successful you gain stunt points equal to the odd colored die to be spent on the current action. Like gaining "mighty blow" which does an extra 1D6 damage. Or bypassing armor. The points must be spent immediately or are lost at the end of the turn.

Stunts can also be combined. For example my brothers rogue once got 6 stunt points. He was already aiming his bow and got his stunt points for an attack roll against one of three hurlocks with crossbows on a wall. He fired off a shot and used 1 action points to "rapid reload" his bow, 3 Points to "lightning attack" to fire off a second shot. Knowing the first hurlock was near death from a mages arcane lance he chose to use his remaining points to disarm the second hurlock.

So in play he fires off nailing the first hurlock center mass and it falls from the wall. His second shot nails the second hurlock on the shoulder ripping back its arm making it drop its cross bow.

I would just love to try it with my next C&C game and see how it goes.