Way back in 2005, a small indie developer by the name of Prairie Games released a little MMO.
No, Not WoW...
It was Minions of Mirth(MoM) and it soon got raving reviews, and a dedicated fanbase.
But the company believed in a 'free to play' revenue model, where you only paid once to get the 'Premium' benefits, instead of bleeding the players dry. So they never had more than the one server. A few years later, development ceased, and back in 2017 the server finally died.
And that was it, we all thought.
Sure, we could still play it offline, but it just wasn't the same.
Now, much of the game was made with tools that either already was OpenSource, or became so later, and a 'stock server' config was at one time available from Prairie Games(so that people could set up their own servers with different rules, and get it linked up to their aauthentication server, even)
Well, some guys took all that and managed to create a working server again, and have a new client that can connect to it. (The old client is hardcoded to connect to the old authentication server)
https://www.reddit.com/r/MinionsOfMirth/comments/myxb44/minions_of_mirth_private_server_client_download/ Oh, I forgot to mention, there's a third faction in the game...
The monsters...
Want to be a big Papa bear(well, black bear) and hug adventurers until they go crunch?
Or a Dragon, and roast a few knights?
Then yes, you can play as those. You just have to finish quests related to those beasts to get a 'template' for it.
Of course, the server is only 'Players vs Environment' right now, not 'Player vs Player', so you can't actually roast other players... yet...