Let's ignore the fact that Everquest is a much OLDER game than WoW. Also ignore the fact that the older game Everquest has a more dated/ancient game engine and dated graphics compared to later games like WoW.
OK, now to answer your question: one of the prime appeals of Everquest, compared to WoW and other fantasy-based MMOs, is that EQ was (at the time) .... the closest thing you had to a persistent Gygaxian/Tolkienesque game world. EQ was a dream for Dungeons & Dragons nerds... because it essentially lifted and copied much of its concepts from D&D. D&D as we all know, in turn, borrowed tons from Tolkien. EQ even borrowed the idea of "alignments" from good ole D&D. It's a surprise that Gygax/TSR/WOTC never tried to sue.
WoW's relations to the original Gygaxian/D&D/Tolkien motif? No so great. WoW was a lot more cartoony, typical of Blizzard's games. WoW's semblance to a Gygaxian/Tolkienesque world is weak at best. Let's just say that WoW is.... uniquely Blizzard.
Can someone please chime in on how Elder Scrolls universe compares? Is it anything like a Gygax/Tolkien fantasy world? Elves/Dwarves/Gnomes/Hobbitses/High-Elves/Humans/Half-Orcs/etc? Or is it bizarrely different and unique in its own right?
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Yes. With Everquest, there was always the FEAR of character death. Players/characters were penalized for dying. Originally, you lost a tiny bit of experience points, and you were forced to do a corpse run. Later patches of EQ kinda "softened" the death penalty, because the cry-babies cried too loud and the Devs finally listened.