The Power Curve is a measure of how the power of a character changes as he levels. Usually in RPGs, characters start off weak, barely able to best a rat, and end up crushing dragons with a single hit.
The Power Curve is a way to describe how great this change is. A steep Power Curve will see end-game characters massively powerful compared to starting characters. A shallow Power Curve sees end-game characters more equal to the starting characters.
Found and copied from rgrd, the following message by David Damerell brings up some interesting points regarding epic fantasy, and the reasoning behind the DnD power curve:
- Don't get me wrong; I like D&D fine as a tabletop game, but only when the type of play is appropriate for those mechanics, not simply when those mechanics are used blindly; and levelling, particularly, is very damaging to an MMO where it ensures that the vast majority of the player base can't actually play together. - David Damerell
- I don't like DnD even as a tabletop game. I hate those leveling mechanics that make one 50th level warrior take on hordes of 1st level warriors, and be able to take an artillery shot "on the breast". - Kornel Kisielewicz
Let's be clear here; even a 20th level warrior cannot take a catapult shot to the chest. It's just that, as long as he has hitpoints left, you'll never hit him with a catapult. The mechanic's a "hit" that does "damage", but what happens in the game world is that he barely escapes it, gets scratched up by debris, tires, pulls muscles...
50th level, of course, is well into epic levels; if you do play up to that level, your characters are demigods, and shouldn't be thought of in human terms.
As for the hordes of grunts, Miyamoto Musashi tackles a couple of dozen guys in Yoshikawa's novelisation, and that's not even epic fantasy; consider the Amber books. No-one would dispute that Benedict could fight a hundred or a thousand ordinary men and win; it's appropriate to the genre.
[But, generally speaking, your umpteenth level characters shouldn't be fighting hordes of no-challenge beasties. There needs to be a sense that your old opponents are still out there and now no match for you, to get a sense of progression and growth - another mistake that MMO*s are prone to is that being a 2nd level character fighting 1st level beasties is not very different to being a 50th level character fighting 49th level beasties. City of Heroes is especially bad here, because the power system tends to mean your character will have essentially the same combat abilities at 10th level as at 21st.]
- I think that such mechanics actually destroy roleplaying. I far much prefere more balanced systems as GURPS... - Kornel Kisielewicz
But you can't do epic fantasy with GURPS, not without a set of patches that make it akin to D&D, because it does have a "realistic" treatment of combat and injury. Sir Lancelot might be killed by Mordred or by a giant, but he's never going to be brought down by a random arrow. This is the old "realism" fallacy; the mechanics want to be appropriate to the genre. If you don't like the genre, that's fine, but don't blame the mechanics for doing their job.
- I think what Kornel mean, as a great fan of his roguelikes in general, is that a fight that involve no risk is no fun. Danger of steep power curve is to ruin the fun by making some fights impossible to loose, and some others impossible to win, while there should be constant challenge. Sure, you can make monsters more and more difficult but what is the point of upgrading both pc and monsters if the result is the same as upgrading none ? As for epic genre, you can make a game with shallow power curve totally epic as long as you don't start with the lame killing-rats-in-the-sewers rpg begining. It's just a matter of design, and balance between frustrate the player by making leveling difficult, and frustrate him by enforcing grinding.