I think the online game I enjoyed the most was Dark Ages. It had a very dedicated style of playing. I had a mentor, which was a supported game mechanism, whom I had a very close relationship to in the game and was very dedicated to training me and making sure that I progressed in the game. It was an absolutely beautiful and timeless roleplaying experience, something I have yet to find in another online game.

It also gets points for being a good 2D isometric game.