BioWare‘s 2002 release, Neverwinter Nights, is a bit of a giant on the RPG scene.
Not only is it a detailed and engrossing Role-Playing Game par excellence, but it also plays host to a huge modding community. It’s also well-known as a multiplayer game too and features campaigns that can be played single or multi-player, and also features Player-versus-Player (PvP) combat.