A DC 20 obstacle has an inherent meaning in the fiction of 5e, across levels and adventures, that stays the same - it is always a Hard obstacle, in terms of the world. That means that if you have a 95% chance to beat that DC, then you are a MASTER at that task because you have reduced Hard actions to mere trivialities. Meanwhile, if you have a 5% chance to do it, then you have a long way to go before you can call yourself skilled at that task, son.
In 4e, a DC 20 obstacle doesn't have an inherent meaning in the world, it is assigned meaning by the DM based on the circumstances it's encountered in. It might be hard for level 1 characters (DM: "Oh, it's an insidious dwarven design made from adamantium!"). It might be easy for a level 10 character (DM: "Oh, it's some rusty tin thing.") It might also have the same meaning (In both cases, the DM describes it as adamantium and dwarven), but that's only by fiat, according to what the DM wants, not inherent to the mechanics.
Two things. First, in 4e, if you can pick the lock of Vecna's safe, then you are a MASTER at the task in question. There is nothing about 4e, or the fiction that it generates, that prevents characters from being MASTERS, or that precludes players from knowing this to be true of their PCs.
Second, your presentation of 4e's DCs is relatively controversial. For instance, nothing in the way the books are written suggests that a DC 20 lock might be both an adamantium dwarven lock and a rusty tin lock. A rusty tin lock sounds fairly easy even for 1st level PCs. And DC 20 is a moderate 10th level DC (in fact 10th level moderate is 21 on the DMG p 42 chart and 18 on the Rules Compendium p 126 chart).
If a 4e GM assigns DCs more-or-less arbitrarily without regard either to the guidelines or to establishing a consistent fiction, then it is true that they won't convey anything about the fiction. But in fact there are guidelines, and I imagine that most 4e GMs do at least try to maintain a consistent fiction. And hence wouldn't set a "rusty tin lock" at DC 20.
The latter design is greatly flexible, because its fiction is largely irrelevant - what matters to the game is the maths.
This is what I am denying. Not the flexibility, but the irrelevance of the fiction.
The fiction is where 4e generates its payoff in play.
In the Neverwinter Campaign book, paragon-level threats are rewritten with Heroic tier stats, so that players can have the full Heroic-Paragon experience (fiction, not so much mechanics) in 10 levels of play. That is a different experience - an accelerated one - compared to default 4e. The flipside is that you don't use 10th level Neverwinter mindflayers and aboleths in a default 4e campaign.
There are other systems out there which make it much easier than 4e to repurpose the same mechanics to new fiction. It could be pretty easily done with Marvel Heroic RP, and is the whole raison d'etre of HeroQuest Revised. But that doesn't make these games about the maths, either. The maths is just a means to an end. And that end is the fiction.
A change in narrative fiction can feel hollow and meaningless absent a mechanical relevance. And the change in narrative fiction between a balor and an orc has little mechanical relevance (more complex, but the same balance).
This "mechanical relevance" thing is puzzling to me. Just looking at the DM PDF for 5e, a CR 17 dragon has about four times the hit points of a CR 2 awakened tree. That seems to correlate, more-or-less, to the four-times damage output of a 17th level compared to a 2nd level character. They also have a 6-point difference in AC, which seems to correlate, more-or-less, with the expected growth in to hit bonus over the course of those 15 levels.
Is it irrelevant to 5e play to fight a dragon as a 17th level PC rather than an awakened tree as a 2nd level PC because the mathematics is roughly the same in both cases?
At the purely mechanical level it's all just maths. 4e has maths. So does 5e. In 4e the bonuses get bigger, and so do the DCs. Likewise in 5e. You can't even begin to identify the difference until you start to talk about the relationship between maths and fiction (eg different principles for setting DCs, or different ways of resolving PCs vs phalanxes), and then we are in a realm where there is no change in the fiction without mechanical relevance. For instance, in 4e gaining levels, and hence experiencing new fiction, has both backward looking mechanical relevance - it is the result of playing the game, which means engaging the mechanics - and foward-looking mechanical relevance - it means acquiring new powers with new effects, adding new feats, adding new PC build elements like paragon paths and epic destinies, etc.
And because of the mechanical minutiae of the system, those changes to PCs have other sorts of mechanical relevance too. For instance, by focusing your PC build in one area you can take your character ahead of the curve; by neglecting other areas you can have your character fall behind the curve, or have to develop new ways of doing things (eg the fighter in my game closes using Might Sprint; the paladin closes using Winter's Arrival, which allows him to teleport adjacent to a marked target).
Fiction differences without significant mechanical relevance are at risk of being irrelevant to the players. If all the balor's aura is doing is making sure I'm of a requisite level to have a regen effect that counteracts it, it's a "different element" that doesn't actually do anything. +15 * 2 will counteract -30 and is different than +2 and -4+2, but if it's always going to come out to be zero regardless, that's just pointless fiddling.
In 5e, if the bonus on my PC sheet is +4 and the DC is 25, I will have to do things in the fiction to either make my bonus bigger (eg find a magic item) or make the DC lower (eg trick an ogre into bashing into the door).
In 4e, if the regen or fire resistance on my PC sheet is "zero" and I know the balrog does 30 hp of fire damage per round, then I will have to do things in the fiction to either give my PC the ability to handle that (eg find a magic item) or to douse the balrog's aura (eg conjure a zone of water).
If buffing my 4e PC so I can handle the aura is boring, why is buffing my 5e PC so I can meet the DC interesting? (Or the converse.) If tricking an ogre into bashing the door is interesting in 5e, why is finding a way to douse the balrog's aura in 4e boring? I just don't see what the radical difference is here. At the mechanical level, it's all just manipulating the numbers. In the fiction, I don't see why 5e's fiction has some engaging virtue (in general) that 4e's lacks (in general).
The former design is not quite as flexible, but it grants that achievement-juice much more directly and with less reliance on individual DMs to patch it up. And it can be turned into the latter system with very little effort.
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Even in a fictionless system, that movement - from +3 to +9 against the same target number - shows at the very least that the player has done some action to move that bonus and has thus given their chance for success a meaningful boost. If a player cares about success (it's a game, roll more than 12), then that's going to be a reward for whatever action they've done, a feeling of accomplishment.
I've played systems with "objective" DCs, and systems with 4e-style DCs, and I can report that in my experience at least there is no innate difference in "achievement juice".
In part because I don't even understand what "doing some action to move that bonus" means, in an RPG, other than engaging the fiction so as to improve your PC. And 4e players do that too. In part because making your numbers bigger isn't always the point of play - just as, now that I am better at crosswords than I was when I was a teenager I don't do the same sorts of crossword I did then, only quicker - instead I do harder crosswords. And in part because an RPG where an important aim of play is to get better at beating the same challenge seems kind of boring to me. As my PC gets tougher I expect to take on tougher challenges, not the same ones more easily.
None of the above is a criticism of 5e's bounded accuracy. Shifting the balance of combat from to hit chances to damage rolls is fine as far as it goes, at least in a system like 5e that somewhat reduces the importance of condition infliction triggered by hitting. But that's just a mechanical tweak. In Rolemaster how high you roll to hit affects your damage, whereas in D&D and Runequest it generally doesn't. That's a mechanical tweak, too, and doesn't make one system or the other a better general-purpose vehicle for communicating player achievement. (Though for some individual players one or the other system might be better, eg if you really get driven nuts by rolling an 18 to hit followed by a 1 on the damage die.)
I mean, if they had to, I dunno, eat increasingly gross things to get that six-point movement, it would be an approval of their gastronomical bravery and their intestinal fortitude.
And 4e players have to have the intestinal fortitude to gain levels for their PCs, too, and hence open up the new fictional vistas of the game. You are taking as a premise that that fictional change is not the result of actual play, or is a "DM patch", when in fact it is core to 4e and the relationship between fiction and mechanics in that system (see the PHB, pp 28-29 and DMG pp 146-47).
IMXP, its systems as presented in the rulebooks rarely tolerate much of the unexpected. Indeed, I find more than a bit of a "tournament" mentality in a lot of 4e: make everything level and equal and remove many of the variables, keep everything smooth, all of those oddities are distractions.
Can you give examples, because I've got not idea what you mean here.
Do you mean the mechanically unexpected? As in 4e breaks down if you build a (notionally) 1st level monster with 1000 hit points? Do you mean fictionally unexpected? As in 4e breaks down if a player declares as an action that (say) his/her PC walks up to the hobgoblin guard and shakes its hand?
I've not had any trouble adjudicating unexpected action declarations in 4e, and indeed feel (between p 42, DMG 2, the skill sidebars in the RC, etc) that I have top notch support in this respect. The mechanical systems - skill challenges, default DCs, expected damage ranges, etc - all make this straightforward. I've linked to some examples upthread, and other ones that come to mind right now are the ranger PC taking charge of enemy hobgoblins' behemoth and riding it across the battlefield; the figher-cleric of Moradin sticking his hands into the dwarven forge in order to aid the reforging of his dwarven thrower artefact; the paladin taming a hostile bear and bringing it along as a temporary companion; one character diving over a cliff to save another who had fallen; and others too numerous to list.
The system genrally doesn't deliver mechanical surprises, in the sense of its mechanics being unable to process action declarations in a way that fits the fiction, or generating outcomes that make no sense within the fiction. You won't have a 1st level PC one-shotting Orcus, for instance (which could almost happen in Rolemaster, though very improbably), or a 20th level wizard's Knock spell being unable to open the latch to a peasant's cottage. But I'm not sure that generating outcomes that make no sense within the fiction is a desirable thing!
In 5e, you could take that balor on at level 10 and come away with your lives if you're clever about it. In 4e (and most earlier e's), you lack the prerequisites for that encounter, so it will simply crush you.
In AD&D level 10 PCs can absolutely take on a Type VI demon!
But in 4e you could easily achieve that result too, if you wanted to, by restatting balors. This is what Neverwinter does (though from memory mostly with aberrant creatures rather than demons). The fact that 5e comes with that restatting already built in is an important fact about it, but not an obvious virtue (eg [MENTION=82106]AbdulAlhazred[/MENTION] was complaining about it upthread) though not an obvious flaw either. As I already mentioned, in Rolemaster a 1st level PC can one-shot Orcus with extreme luck. Does that make RM an even better vehcile for accomplishment than 5e? Not that I can see.
I don't think I do know what you mean. If the mechanics fall away, then they don't do much support, they just disappear and are subsumed into the fiction and thus become pretty meaningless. Mechanics that are generic to the point of supporting "many different fictions" are not good at evoking one specific fiction (and vice-versa).
What [MENTION=82106]AbdulAlhazred[/MENTION] means is pretty clear to me.
He means that the mechanics don't, on their own, determine the fiction. You can use 4e's system to play a Neverwinter game - go from zero to mindflayer killer in 10 levels - or a default game - go from zero to mindflayer killer in 20 levels, then take on Demogorgon by level 30 - or to play a Dark Sun game, where even at 30th level you are still confronting more-or-less mortal threats. To achieve this all you have to do is rewrite, or relabel, the monsters (which is what Dark Sun and Neverwinter do), and have the GM change the way s/he adjudicates and applies the fiction.
Gamma World is another example of the same phenomenon, but moving sideways rather than compressing or expanding: the same mechanics support a different, post-apocalyptic mechanical overlay.
In other words, the mechanics are not coupled to some determinate fictional elements from which they can't be stripped. Coupling has to take place, by creating monsters, traps, default DCs for doors/locks/jumping distances/etc, and the like. This is what 4e's monster manuals (both the core, capitalised ones, and the variant ones like Neverwinter or Dark Sun) do.
That doesn't mean the mechanics are irrelevant to play, though. They actually settle action resolution. A game of default 4e, or Neverwinter, or Dark Sun, or Gamma World can't get going until the players and/or GM start to engage the mechanics.
4e is not the only RPG that has this sort of feature. HeroQuest revised does. So does Marvel Heroic RP. And I imagine plenty of others that I'm not as familiar with.