-A server that's semi-associated with an old GameFAQs board. The board has become pretty shit over the years and most of the people in the Discord server don't post there anymore, and we've formed a pretty strong community. Only one I'm notably active in.
-A couple of Melee-related servers. One about statistics for the competitive scene, one for my alma mater's scene. I'm semi-active in these I guess, lurk more than anything.
-....A few porn/kink/sex thing related servers >_>. Mostly femdom related. In 2017 there was a like two month period where I legit spent most of my free time on one of these, don't ask how that even happened. After that I realized I was spending too much time on Discord so I stopped going a lot, and then by the time I came back it was kinda dead. I joined a few others to fill the void but none of them were as good as that one was, so I mostly lurk occasionally in them.