Care to explain what makes the magic system special?
Well, I'll take one facet of combat - mob splitting. In order to control the pulls, you need to pull singles. There's a number of techniques you learn that exploit the mechanics of aggro. One of them is feign death pulling, and I'll use the Necromancer class as an example
1) You cast Snare, a movement slowing spell that also has a DOT component on your target
2) Its in a pack, so it brings its friends and they charge at you
3) Just as they reach you, you cast Feign Death and fall to the ground
4) They all stop, turn around and walk back to their spawn point and 'reset' (they drop aggro)
5) The mob you hit with Snare is far enough from its spawn point (remember its movement speed has been halved so its about halfway between you and the other mobs now) so as not to chain aggro the other mobs, and when you stand up again, it continues on towards you, because that DOT component was still ticking preventing him from resetting
Thats it, you've separated the mob you want from the pack, and can take it out safely. You then rinse and repeat with the remaining mobs.
So thats one technique used in pulling - feign death. Another one is pet pulling, where you summon a low level pet, send him into the pack of mobs and immediately call him back to you after he hits the mob you want. The pack won't come after you as long as you pull the pet away before its killed (you need to buff your pet so it will survive) and as long as the pet is of a low enough level, that way it won't aggro the other mobs. But, the mob your pet hit will follow your pet back - to you. Again, you've pulled the mob away from the pack and you finish it, then rinse and repeat.
There are other techniques and tricks dealing with combat, navigation, and general engine mechanics that were never an intended part of the games design, such as sit aggro, body pulling, fear kiting, quadding etc. You could very nearly write a book on EQ's emergent gameplay, and there was a surprising amount of depth to EQ that you only got to experience once you've been playing it for a while. I don't think the devs were ever really happy about a lot of it - some of the really exploitative stuff would land you a ban. But most of it was really just about being resourceful, at least that was my view, and I didn't see it as cheating. EQ was very time intensive, and a lot of these tricks came about by trying to save time.