Aaron L said:
I haven't seen anyone saying that it's perfect. What I have been seeing is people defending it against others who are calling it completely worthless.
I don't think its completely worthless, though I do understand the position of people that do. The problem with CR is that it is not very fine grain. Not only is there no such thing as CR 5.6 or CR 4.3, the CR scale is logrithmic. So a CR 8 challenge is not 'just one point' harder than a CR 7 challenge, but something like 50% harder. This means that if the CR is off by as much as one, its a pretty big deal. If it's off by two, its a really big deal. And likewise, a CR could arguably be correct - it could be the best number that we can come up with - but the difference between a CR 7.5 monster and CR 8.4 is still pretty darn big.
I haven't had any problems with CR since I've been playing 3.X. It's worked very well for me.
I have had all sorts of problems, though admittedly 3.5 gives somewhat better guidelines than 3.0.
Part of the problem is that I use alot of advanced monsters and alot of templates. I've found that alot of the time if you do this, you can hide the monsters CR because the advancement is synergistic (in addition to making the monster all around tougher, it elimenates some critical disadvantage that the monster had) or the template similarly covers up weaknesses that the monster had. In playing, I've found you sometimes have to fudge the CR up a point or two.
Another problem is not so much with the rules as written but the inherent limitations of the rules as written. The RAW say, 'No more than 12 creatures'. Now, I can understand the basis of that advice, but sometimes you want to design an old skool encounter and sometimes an old skool encounter occurs just because the PC's stumble into despite your design. The RAW written say, 'More than 12 creatures' is tricky and leave it up to the DM to decide. I can deal with that, but its something you can't get the rules to help you on.
What I've found is that the rule that doubling the number of monsters increases the EL by +2 works well only for creatures with a CR that is relatively high in comparison to the PC's. For creatures with relatively low CR's, doubling the number of monsters is closer to EL + 1 not +2. I'm not sure what rule you would use, if even a good one can be devised, but the problem is there. It comes from the fact that when the monsters need a 15 or more to hit, and/or the PC's only fail saves on a 5 or less, the difference of one or two points means a big big deal. It's not such a big difference if something happens 50% of the time or 60% (or 40%) of the time. But as you get closer to 20 or 1, funny things start happening. Needing to get a 19 is 50% 'harder' than needing to get an 18. Needing to get a 20 is 100% 'harder' than needing to get a 20. When you get on that part of the curve, the difficulty of the encounter goes exponentially down and its not really as tough as the EL suggests. This happens most often in my experience when you are in a campaign involving some mook villain race (orcs, gnolls, goblins, whatever) and in the space of just a level or two the PC's get up on the curve. When that happens, doubling the monsters doesn't work.
The problem is that the CR/EL system suggests that it does. For example, it suggests to a novice DM that 8 gnolls (or 1st level human fighters) is EL 7. But whether it really deserves that rating depends alot on the player level. If 3rd or 4th level characters go up against 8 gnolls, I'll award the full XP for a very tough EL 7 encounter. But by 5th level I'll probably treat it as EL 6, and by 7th level or higher I'll probably only award XP for a EL 5 encounter. This is because the rewards on the XP table are going up in a linear fashion, but the difficulty is actually going down exponentially. The lower award better represents the challenge of the encounter.
The biggest problems of all though relate to adding classes to monsters or PC classed NPC's. In brief, adding PC classes usually doesn't increase the CR by a flat 1 per level. There are a couple of ways to see this. Lets start with one of the obvious. Adding 2 HD of dragon or outsider to a creature increases its CR by 1. But dragon and outsider are really powerful 'classes'. Dragon gets d12 hp, good saves, full BAB, and above average skill points. Outsider trades d8 hp for even better skill points. PC classes lose out to this. Six levels of fighter just don't add as much as 12 HD worth of dragon or outsider do. The few extra combat feats you'll pick up just don't make up for the missing +6 attack bonus, much improved will and reflex saves, vastly superior skills and 50 or more odd hit points. You could spend alot of feats just trying to make up for any one of those things. Clearly even adding a relevant class to a monster isn't necessarily increasing its CR in a one to one fashion.
And the same thing is true of adding PC's classes to human, orc, or any other base creature. PC's classes are really good. But they aren't that good.
At best, in my experience a PC class is about character level - 1. An 8th level fighter or barbarian is probably CR 7. But support classes are probably lower CR than that in most cases because so much of what balances them with a more combat oriented classes doesn't really impact a combat. A 8th level bard, cleric, monk, or even rogue is probably more like CR 6. On the other hand, a bard or cleric might be worth thier full CR if they have a supporting cast or are part of one. Spell casters are tricky and depend alot on spell selection. At low levels they tend to be closer in power to support characters. At high levels, they tend to closer in power to combat characters.
NPC classes are closer in power to class level/2 or even class level/4 than CL - 1. A 10th level warrior is much closer to CR 5 than CR 9. Again, warrior isn't remotely as powerful of a 'class' as dragon or outsider.
In addition to all of that, it would be nice if there were at least some suggestions and reminders for what happens with non-standard treasure. Suppose I give an Ogre an extra 900 gp worth of equipment, or 4500 gp? Doesn't this make a difference. What if the 10th level fighter has the equipment you'd usually expect of a 5th level fighter, or even a 1st level fighter?
To give you an example of the sort of problems I run into, its not uncommon for elderly women in my campaign world to be level 9 commoners with STR and CON around 5 and little combat equipment to speak of. They have combat ability more in line with CR 1/2 or 1/3 (or less), but if you don't treat the CR/EL system as a guideline you would end treating these as CR 8 individuals. Of course, I don't expect anyone to be so silly, and I expect most DM's would not award XP for killing harmless little old ladies, but that's using your judgement and what I'm saying is simply, "Use your judgement. If it doesn't make sense to you, it probably doesn't make sense."