User blog comment:Pualover/Overlord Power Level/@comment-35206516-20180510095606/@comment-45.56.46.26-20180602062403

Anybody can, but there are some innate problems, as the narrative has shown multiple times. There are several good discussions about what difficulty ratings even really mean and the ptifalls of assigning and using them. There's a good one in Vol 7 when Fluder and his disciples are discussing why he can't control the Death Knight. It's especially relevant because we already know that many of the Death Knights defensive abilities (probably including spell/turn resistance) are disproportionate to its level, in exchange for the offensive abilities being below level.

So a Death Knight would be difficulty 120 or more if you were attacking it, but only 90 if you were defending (except that it won't ever get tired and you will, at which point you'll be easily killed).

Also, New Worlders seem to have the ability to gain some abilities (such as Martial Arts) without fixed correlation to leveling, and also seem to be able to gain some advanced class levels that should only be available at highter levels in Yggdrasil (which breaks the normal relationship between levels), and on the other hand often have unoptimized builds composed of a mix of fairly low level classes that don't 'stack' well (Neia is given as an example).