TheCosmicKid
Hero
I mean in-universe. Does group number ten have an opinion about the fact that groups one through nine got slaughtered? Why didn't they either mass their forces better or run away? Were they unaffiliated? What are the odds of adventurers running into ten unaffiliated groups of monsters in five hours?No, they were all low-level fights and we run fast. There's not exactly much to run on a kobold or a guard.
And I'm also trying to understand your math here. If they really were all guards and kobolds, by my reckoning that's 260 kills per character to get to level 5. You say you also gave some quest XP, but unless the quest XP dominates the total (in which case, there's your problem), we're still talking hundreds and hundreds of kills. In five hours. Those are figures Rambo would struggle to hit, and he's got automatic weapons. How many people in the history of the world do you figure have managed to kill, hand-to-hand, two hundred actively resisting opponents in five hours? If nothing else, don't you think they'd get tired?
What I'm saying is, if the pace of the slaughter in your game is so... accelerated, any conclusions you draw about the rate of XP advancement are bound to be a little skewed.