Some parting notes (vol. 1)

I've gotten some neat feedback on the alpha draft and realized that there were some things that I never got around to including in the PDF. I figured I'd share them real quick for the sake of completeness.

Throughout Runeward I had a couple of design ethos. One of those ethos was that consistency of mechanics leads to quicker familiarity and mastery of the system. At the same time, though, sometimes it is a good idea to make things feel special. Breaking the mold or having a completely unique mechanic for something that is supposed to be rare helps emphasize that and set it apart. One such mechanic was Runeward's miss chance.

I preferred 3e's miss chance mechanic over 4e's. The flat percentage on top of AC was just a neat little addition that set it apart. It really made you feel like you were firing through fog or that the monster was phasing in and out of existence. It was also fun (probably properly read as frustrating) for people to realize they rolled high enough to hit but still end up missing because of the miss chance. That is a good mechanic, the character was successful (which feels good) but that success was mitigated by some thing in-game (which feels horrible). A flat increase to what you need to roll on a d20 just can't compare.

Percentile miss chances also have a problems. The linearity with which they decrease your likelihood to hit was perhaps too rapid. It also only ever allows for 10 steps of missing (e.g. 10%, 20%, etc) with a lot of those chunks being either too low to matter or so high they are prohibitive. The "fun" miss chances are few and far between. Finally, a miss chance connotes the idea that you don't know what is going to happen. When it is then a straight percentage it doesn't really feel like a 'chance,' it feels like odds.

Miss chance in Runeward sought to address those issues.

You can acquire a miss chance from a range of scenarios (cover, concealment, or creature ability) and they all stack together. So if I am firing through fog (hypothetical 2 miss chance) and through brambles (hypothetical 3 miss chance) at some creature with a stance that increases all miss chances by 1, that would quick add up to 6 miss chances. So far, fairly simple.

The second step was to calculate your miss chance die. For the most part this was a function of the range at which you were interacting. At close or melee range you would default to a d10, at short range a d8, and at long range a d6. For example, a longbow being fired through fog at long range would roll a d6 but if the target was changed to short range (adjacent zone) it would increase to d8 and if you fired on someone in the same zone it would be d10. There is also a Blind Fighting feat that increases your miss chance die one step for all weapons.

The final step is to roll your miss chance die for every miss chance you have. To continue the example, our hypothetical longbow firing through fog and brambles at a shifty creature (6 miss chances) would roll 6d8 if the target was in an adjacent zone. If any of the dice come up a 1, the shot misses. In this way, a larger die is a boon because it is less likely to come up a 1.

Let's see some math!

		Miss chance die type
		d6	d8	d10	d12
# miss chances	1	83%	88%	90%	92%	Probability to hit
	2	69%	77%	81%	84%
	3	58%	67%	73%	77%
	4	48%	59%	66%	71%
	5	40%	51%	59%	65%
	6	33%	45%	53%	59%
	7	28%	39%	48%	54%
	8	23%	34%	43%	50%
	9	19%	30%	39%	46%
	10	16%	26%	35%	42%

Our longbow on 6d8 has a 45% to still hit (and then a 55% chance to miss). If he instead tactically shifted to be in the same zone as the target, his die would jump to d10 and he would hit 53% of the time. Finally, if he had Blind Fighting and shifted into the same zone, he would go up to 59%.

The reason I like this model is four-fold.

1. It puts more power into the hands of the player and makes miss chance more tactical in nature based on placement.
2. It allows for more sources to add together into a simple miss chance model. Unlike with a flat percentage where you only have 10 steps possible (and most of those aren't in a dramatic zone), almost all of the results with this model have a meaningful measure of tension.
3. The actual odds are semi-hidden from the player. In fact, the odds feel much worse than they actually are. Telling someone to roll 6d10 and they fail if *any* dice comes up a 1 feels like bleak odds yet you'll probably succeed. That is going to make players feel great.
4. It adds a lot of tension. You've already figured out you hit and now you are rolling miss chance. If the likelihood of missing is low (e.g. one or two dice) then it is quickly resolved and we don't spend much time. If the likelihood of missing is high (e.g. 6+ dice) then it organically gets drawn out with each successive roll raising the tension until you either succeed or dramatically fail.