uhmm, i like the auto battle feature of it.
the mercenary system will rack your brains out cuz there is a near endless possiblity of mercenary combination/party composition. this feature actually makes you think about strategies, your offense, defense and counterattack.
the guild, town and nation system is quite different from your usual mmo social groups
im still new to this game (lvl69) and so far these are the reasons that keeps me playing it...aside from the fact that its free