In NWN2 the Level Cap is 20, but you can multi-class between 4 classes. If you want each class to be the same level then you'd only get to level 5 of each class. I consider that to be a low-level character even if the character is 4 classes.
I think it would be a good idea for that level cap to be removed or altered so it's not such a nuisance. Maybe make the level cap higher so characters can reach level 40 or 60, with or without multi-classing. That way characters could get stronger, and to keep the game fair perhaps certain monsters should be tougher or maybe a mod could be made so that the monsters level up as the character does.
I'm not sure how it should be done because I don't make mods, but it seems to me like this would be a good idea.
The level cap is hard coded in the game executable; while it is possible to gain XP in such amounts as to exceed level 20 (or 30 if you own Mask of the Betrayer) the game engine will not allow you to progress in level beyond the cap.
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