Look, let’s make this very easy: Click along to GOG.com and go download Neverwinter Nights Diamond right now unless you’re reading this on December 3rd or later. It’s free as of right now, and it will remain free for another 48 hours. Come back and read the rest of the post after you’re downloading! Seriously, go do that.
Why is this so important to us when it’s not an MMO? Because if you have the slightest experience with MMO history, you know that the online play components of Neverwinter Nights have had an enormous influence on MMOs and their popularity. Heck, there’s some title or another that is an MMO based specifically on this game, although the name escapes us at the moment. Probably starts with an “N.”
And again, it’s free. Actually 100% free-free, especially since it’s on GOG.com. There’s even a helpful post showing off some particularly well-loved mods for the game. Go ahead, download it. You’ll be glad you got it for free later.