Any challenging mmos or multiplayer game suggestions

Donpoohbear

ive been enjoying darksouls but i really enjoy interacting with ppl online.  so any mmo that is challenging and not just a grindfest. or something like borderlands 2 were i can play solo or join a group of ppl would be good but not diablo.

sunandshadow

Hmm.  The combat in Dofus is pretty mentally challenging, but personally I'd still consider it a grindfest since it has no quests above about the first 20 levels (of 200 or so)