What were/are your favorite old school mmo rpgs, and why?

Mine was and still is Dofus (love the community, love the world building, ankama has such a rich universe! And the combat system has really nice strategic mechanics without being too hard) but I also liked casual mmos/ chatrooms like habbo hotel (because i could just log in and chat, and the customisation of your character and home were really fun). And could we consider club penguin? (Idk the mini games were so fun and the chat… well.. for kids but still nice. Also liked the fact it’s penguins haha)