D&D 5E Stupid math stuff that vaguely pertains to 5e.

[B.T.]

This may need to be moved, but here's my question: as a baseline measure that ignores all situational modifiers and presupposes an "average" adventurer, what should the chance of success with an action?

That is, how often should the average fighter hit with an attack? What about the average rogue? How often should a saving throw succeed? How often should characters succeed on skill checks that they are good at? What about skill checks that they're not good at?

As a side note that vaguely pertains to this vaguely-pertaining question: should characters be differentiated more by their chance of success or what they can do upon succeeding? For instance: should a fighter and rogue have similar hit chances but the fighter can do some sort kind of special maneuver that adds rider effects? Or should the game be simplified so that the fighter hits more often?

 

[I'm A Banana]

It's a simple question with a pretty intricate answer, so it'll be interesting to see the responses!

The most basic of chances that allows for character variation would give you a three-point system (25%, 50%, and 75%), but maybe you want to cluster them closer to 50% (40%, 50%, and 60%) to keep the dice roll significant. You might also make a five-point system to get more detail (40%, 45%, 50%, 55%, 60%), or more extreme (30%, 40%, 50%, 60%, 70%).

I'm kind of fond of that last one, actually....

And then, do you weight the game in favor of the party or not? Do you let a coin flip determine their fate? Or do you give them, say, a 66% chance of success out the gate because "they're heroes" and your game wants to encourage the party to win more often? Or do you maybe give them more like a 33% chance to start out with, they'll probably fail with die rolls, and then let them tweak the odds with things like Advantage?

The odds of success have varied pretty significantly over the course of the editions, from 4e's "assume the PC's are victorious, basically," to 1e tournament play grindfests like the Tomb of Horrors. Controlling that feel -- the feel of deadliness, or of challenging play -- will be a pretty important tool for 5e to have.

 

[Giltonio_Santos]

Taking into account an enemy of equal power level, I believe the following:

- The fighter should have 80-75% chance of hitting on a swing of the sword.
- The thief should have about 60-55% and increase that to same as fighter when using any backstab-like class feature.
- Enemies should fail 80-75% of the saving throws against a wizard's strongest spells.
- Cleric should have about the same as thief, improved by spells instead of combat circumstances. Enemies should fail 60-55% of the saving throws against their strongest spells.

I don't like the idea of "balanced" skill checks. I hate when 20th-level characters keep facing rivers that no peasant could swim and walls that no 1st-level thief would be able to climb, for the sake of keeping increasing skill modifiers relevant.

Cheers,

 

[Savage Wombat]

Those sound too high to me. Do we want a 1st level sword fight vs. an orc to come down to who wins initiative?

 

[Kynn]

Those sound too high to me. Do we want a 1st level sword fight vs. an orc to come down to who wins initiative?

It's hard to get the right balance between "the guy who goes first, hits first" and "combat is a whiff-fest".

In a typical AD&D fight at first level, you've got a THAC0 of like 20 and a +1 or +2 bonus, and you're fighting something with an AC of 5 or so. That means you hit about 1 attack in 3 (and the orc likewise has the same chance to hit or miss). That seems a little too whiffy for me.

In 4e D&D, you've probably got a +8 or +9 bonus to hit (+4 ability score, +3 proficiency bonus, +1 feat bonus) vs. an AC of 15 (14 + level, assuming a skirmisher opponent) which means you end up hitting 2/3 of the time.

My ideal would be somewhere between these two extremes, meaning that you'd hit like 50% of the time.

BUT!

I am okay with starting out at a low chance to hit against level-appropriate AC and then having BAB scale faster than AC does. I am okay with the formula looking something like this (assuming level-appropriate AC):

level 1 ... hit 40% of the time
level 4 ... hit 45% of the time
level 7 ... hit 50% of the time
level 10 ... hit 55% of the time
level 13 ... hit 60% of the time
level 16 ... hit 65% of the time
level 19 ... hit 70% of the time
etc

I want higher level characters to hit more often than low level against appropriate foes, and I want this math to be baked into the system and balanced appropriately.

4e assumed a constant hit chance (such that your chance to hit an appropriate foe at any level was roughly the same) and I think that was a mistake. Earlier editions like AD&D didn't assume this, but didn't have very tight math. I want tight math WITH this assumption, and monsters built accordingly.

 

[BobTheNob]

Those sound too high to me. Do we want a 1st level sword fight vs. an orc to come down to who wins initiative?

Its a ibt of a bummer that. The more you up hit probability and damage, the more you make initiative the dominant factor. The more you decrease hit probability and damage the more combat drags on.

Its such a fine balancing Act. I have always considered 50-50 all things being equal

 

[Ratskinner]

That is, how often should the average fighter hit with an attack? What about the average rogue? How often should a saving throw succeed? How often should characters succeed on skill checks that they are good at? What about skill checks that they're not good at?

As a DM, when I have to eyeball it, I generally follow a 90-70-50-30-10 rule (for d20s: 2-6-10-14-18). Corresponding to Very Easy - Easy - Typical - Hard - Very Hard. Failure has to have some very entertaining consequences for me to ask for Very Easy and sometimes Easy rolls.

As a side note that vaguely pertains to this vaguely-pertaining question: should characters be differentiated more by their chance of success or what they can do upon succeeding? For instance: should a fighter and rogue have similar hit chances but the fighter can do some sort kind of special maneuver that adds rider effects? Or should the game be simplified so that the fighter hits more often?

I prefer the latter. Highly variable "chance of success" would (I'm guessing) mean players grubbing for every "+1" they could find, and the effective power curve being very steep. Adding more options and broadening the results of the success means less of that, and I'm in favor of less of that.

 

[Mokona]

The average roll needed to hit should be higher at first level and slowly decline as you level. So you get "better" at hitting average opponents as you level. Exact numbers don't matter at this stage but say you need a 13 to hit at first level and you need a 8 to hit at 20th level. At first you really want combat advantage because it gets you closer to 50/50 and over time you can afford to take penalties for environmental effects (or extreme action) and still hit 50/50.

The gap between skilled users and non-skilled needs to get narrower. In 3e that gap started at a +8 spread and got eternally wider. In 4e the spread also started out at around the same level (+9) but only increased slightly after that. Both of those ignore Skill Focus feats which widen the gap in favor of specialists. I would hold it down to a skilled-unskilled gap of only +2 and then let specialists really shine by handing out +5 for Skill Focus.

Hitting is fun. All player's should hit roughly the same amount of times if there is any binary effects (riders like status effects, penalties, marks, zone control, &c). If hits only convey damage then it's ok to design a system where those who do more damage hit less often and vice verse (but I think such a simplified system with 5e is unlikely).

 

[KidSnide]

I think if you do research about what players find fun in actual play, you get results that are very different from 50/50 chance of success.

To take a trivial (but often misunderstood) example, PCs need to have a dramatically better than 50% chance of succeeding at an average encounter. Otherwise, you get unacceptably short campaigns as 99.9% of them will end in the first 10 encounters.

If PCs hit only 50% of the time, players will feel like they were completely ineffective in combats shockingly and unacceptably often. Even low-accuracy characters need to hit more than 50% of the time, or the experience will be unbearable. The consequence is that high accuracy characters will hit almost all the time. That's OK. That's the benefit of high accuracy.

Post-math-fix 4e got this mostly right, at least in the heroic tier. I have high hopes that 5e will adopt at least some of that wisdom.

-KS

 

[Gansk]

Trailblazer has come to the conclusion that the PC's should succeed around 70% of the time for the game experience to seem neither too easy nor too hard.

3e is measured against this goal for the following when PC level = monster CR

PC attack vs. monster AC
PC AC vs. monster attack
PC save vs. monster DC
PC DC vs. monster save

Buy the pdf if you want to know how the math turns out.