[Luvian]

The 2nd edition had progression up to level 20, level 20 being considered a great hero that could take on pretty much anything. Then they made a supplement book that created a system of rules for levels above 20, which I bought but never got to use, as my oldest campaign that was 2 and a half years old and we played every weekends only had players in the level 12-15 range.

Then in third edition, they added those epic rules in the base game. But they work a little differently from regular levels. Out of memory, epic levels don't give you more health, and they're not exactly called levels I think. Your sheet still said level 20 warrior for example, but then there was a second number for epic levels. Something like that.

20th level characters are supossed to be rare, these are the greatest heroes, Drizzt that in the Forgotten Realm is considered to be one of the greatest heroes was around level 12. So epic level characters are the heroes's heroes. That's the demigods realm and should be out of the reach of all but a tiny fraction of the the greatest heroes ever known to that world.

They raised the level cap in NWN because let's be honest, action rpg players really like to powergame and like big impressive numbers and kicking the crap out of everything, but that's not Dungeon and Dragons.