D&D 4E Showing the Math: Proving that 4e’s Skill Challenge system is broken (math heavy)

[Ulthwithian]

Aegir: But it doesn't. If you see my previous post regarding this, you'll note that 'around 11+ to succeed' seems to be the reigning success paradigm in 4E. As such, that puts the DC15 check right aroung the correct mark for an attack. Note that the AC modifier is +2, the same as the normal weapon proficiency bonus. In that vein, if you have a trained skill and either a +4 bonus from your ability or a +2 bonus from ability and a +2 bonus from race (which seems to be the norm), you get a +9 on your skill check. That means that the average DC for a skill check at 1st level should be 20, not 15.

Table of normal modifiers:

Ability: Assume +3
Proficiency (combat only): +2
Trained (skill only): +5

If you assume an 11+ to succeed is the base, that means that the norm to succeed on a non-AC, non-skill check should be about a 14, an AC attack should be 16, and a skill check should be 19. These are all within 10% of the actual numbers suggested (and if you assume a +4 modifier, it actually is correct).

Therefore, I believe that the only logical conclusion is that the table is correct. Some other part might be missing, though.

 

[Tuft]

Well, a good example in the DMG would have made a lot of difference. Or a published scenario that uses a proper set of skill challenges to illustrate them (and other appropriate non-combat stuff.)

Seems like the success of skill challenges depend heavily on the PC.s having the right feats and the right bonuses, though, which makes you wonder how skill challenges in published scenarios are going to fare, as they are created in advance by someone who doesn't know the strength and weaknesses of each individual party. And in 4E you cannot nip down to your friendly magician's guild to purchase a scroll with a boosting spell that patches up any unexpected weakness the party has, so that the adventure can continue. (Yes, I know that a lot think that is a Good Thing... )

 

[Spatula]

I honestly haven't read the entirety of this thread, but to my knowledge, this hasn't been brought up yet. There are two things that, when taken together, suggest that the assumption ("For skill checks: increase DCs by 5") is the main flaw in this entire argument.

DMG, p73: "Set a level for the challenge and DCs for the checks involved. As a starting point (...) use moderate DCs for the skill checks (see the Difficulty Class and Damage by Level table on page 42)."

Keep on the Shadowfell, p52 (Talking with Keegan): "In order to change his mind, the PCs have to converse with him and, in the process of doing so, succeed on four separate DC 15 skill checks before they fail four such checks."

Now, for an assumption: this encounter was in fact designed using their own rules for Skill Challenges.

Not exactly by the rules in the DMG, since the KotS challenge allows for 4 failures for 4 successes (vs 2 failures for 4 successes). But yes, this was brought up earlier in the thread. Along with the web enhancement skill challenge, which does use the +5. So which is right, and which is using an earlier or incorrect version of the rules?

 

[silentounce]

DMG, p73: "Set a level for the challenge and DCs for the checks involved. As a starting point (...) use moderate DCs for the skill checks (see the Difficulty Class and Damage by Level table on page 42)."

Keep on the Shadowfell, p52 (Talking with Keegan): "In order to change his mind, the PCs have to converse with him and, in the process of doing so, succeed on four separate DC 15 skill checks before they fail four such checks."

Now, for an assumption: this encounter was in fact designed using their own rules for Skill Challenges. If this is the case, then the call for DC 15 checks is in fact a "moderate" challenge, which places it squarely in the 10/15/20 range that the p42 table presents, without the +5 applied.

Well, you also have to contend with this though: http://wizards.com/default.asp?x=dnd/4dnd/20080522b

Flat out states that that is a 6th level challenge. Gives DC of 22 for primary skills. Now if you look at the chart on page 42 of the DMG, there is no 22 in the 4th-6th row, but there is a 17 as the moderate entry. And 17 + 5 = 22. Next, the other two skills listed for that challenge have DCs of 18, which is 13 + 5. 13 is the number in the easy DC column. Obviously, when they created this challenge they used the table on page 42 with the +5 modifier for skill checks. Any other way to come up with the numbers they give is too convoluted.

Note the author of that skill challenge. I'm assuming that the R&D Director should know the proper way to build a challenge. Given this, it appears that the challenge with Sir Keegan was assigned an "easy" difficulty which would be a DC of 10 for 1st-3rd levels, adding a +5 for skill check would give you the DC of 15 given in the text.

 

[Plane Sailing]

Perhaps the 'saving grace' that the designers anticipated for the system is that 'failure' of a skill challenge may mean that you succeed the task but with future implications?

e.g. in Escape from Sembia, there was a skill challenge to escape. Win or lose at the skill challenge, you still escaped... it is just that if you lose the skill challenge a future encounter gets the jump on you, rather than vice versa.

I can imagine that it might be quite difficult to get into the mindset of creating skill challenges where the results are not "succeed/fail" but instead are "degrees of success".

(caveat: this is on the basis of the skill challenge previews, etc; I've not been able to go through the DMG yet)

 

[Hambot]

I think the Designers understand the normal skill system very well.

But when you track the cumulative probabilities and demand twice as many successes as failures the math becomes very deceptive.

From looking at all of these results I do feel there are hidden "grappling" rules buried away in here that only a mathematical analysis uncovers.

If you want to run the system as given you should probably start with all skill uses being easy before cranking up the DC's when you know what you're doing.

I'm just trying to figure out how to run these with a 1 PC party - aid another is not an option. I think I'll just give her silly high ability stats to make her PC robust enough to get through a challenge, then try the original and Stalker0's systems to figure out what works better.

 

[Plane Sailing]

2) The players can't choose the difficulty of their checks. The easy-moderate-hard is set by the challenge itself, per skill.

Re-reading - you're completely correct. In fact, I don't know where I got that idea - perhaps some early pre-release interpretation?

I had that idea too (that PCs could choose to gamble on an easy check with harsher consequences for failure, or risk a hard check to get extra benefits).

It doesn't seem to be in the Excerpt on skill challenges, so I wonder if it was in Keep on the Shadowfell??

 

[Boarstorm]

http://www.enworld.org/showthread.php?t=230233

Very interesting read. Since he isn't pimping his own thread here, I will.

Edit: Plainsailing -- that was from some DM's running of Escape from Sembia, and it migrated onto these boards from there when one of the attendees posted his own skill challenge involving a trapped body hung from a tree.

Whether it was from a prior iteration of the rules or the DM in question merely misread the quick rules he was handed is something no one without an NDA knows, I imagine.

 

[Darth Cyric]

Two words: Gambler's fallacy.

 

[gribble]

I'm afraid I don't understand what you're getting at.

Clearly not.


I'm categoricaly not saying:

1. That rolling to assist another PC is less fun than not making a roll at all.
2. That we're ignoring or only using part of the rules (as should be clear when I say that we *were* rolling to assist).

What I am saying is that it seems (both mathematically and empirically) that for players who aren't trained in one of the primary skills of a skill challenge there is only one viable option: rolling to assist those who are trained in one of the primary skills.

I.e.: skill challenges in 4e are not a new and revolutionary system - they are effectively glorified 3e diplomacy checks. The player with the highest modifier in diplomacy makes the primary roll and the other PCs assist him. If he manages to make the opponents friendly (i.e.: X successes) before he makes them hostile (i.e.: Y failures), the party succeeds. This is no more (or less) fun than it was is 3e... and given that skill checks are often lampooned as one of the "unfun" parts of 3e... well, I'll let you make your own conclusion.

And before the inevitable chorus of "but the players can use *any* skill for a challenge, not just the best one" pipes up, I'd like to point out that the rules and examples in the DMG are very clear that isn't really the case. Claytons choice isn't really a choice. Of course you can house rule it, but let's not confuse that with the RAW.